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Centered gnomonic numbers
The centered gnomonic numbers are the centered equidistributions of dots, restricted to a = 1, which is the only case where all positive integer values of b are coprime to a, and where b is a positive integer, (Cf. gnomonic numbers,) thus the resulting b-step centered gnomonic numbers are given by:
- , when b is odd positive integer,
- , when b is even positive integer;
or more compactly:
or even more compactly:
The two cases are explained as follow:
- when b is even positive integer, is always odd, so when centered, any previous dot is masked by a new dot, thus we get dots as a result;
- when b is odd positive integer, is alternatively odd then even:
n = 0: O gives 1 (central "O") dot since 1 is odd, n = 1: e ... e e e e eOe e e e e ... e gives 1 "O" + (1+b) "e" = 2+b dots since 1+b is even, n = 2: o ... oeo ... oeoeoeoeoeOeoeoeoeoeo ... oeo ... o gives 1 "O" + 2b "o" + (1+b) "e" = 2+3b dots since 1+2b is odd, n = 3: e ... eoe ... eoeoe ... eoeoeoeoeoeOeoeoeoeoeoe ... eoeoe ... eoe ... e gives 1 "O" + 2b "o" + (1+3b) "e" = 2+5b dots since 1+3b is even, ... ... ...
so we alternatively mask the dots of a given parity (with 2b more, for n ≥ 2) while the dots of the other parity remain untouched, thus we get dots as a result.
All figurate numbers are accessible via this structured menu: Classifications of figurate numbers
Contents
- 1 Formulae
- 2 Schläfli-Poincaré (convex) polytope formula
- 3 Recurrence equation
- 4 Generating function
- 5 Order of basis
- 6 Differences
- 7 Partial sums
- 8 Partial sums of reciprocals
- 9 Sum of reciprocals
- 10 Table of formulae and values
- 11 Table of related formulae and values
- 12 Table of sequences
- 13 See also
- 14 Notes
- 15 External links
Formulae
The nth b-step, or B = b+1, centered gnomonic number is given by the formula:
where
The choice of for labelling the centered gnomonic numbers is motivated by the patterns of the (1,k)-Pascal triangle and the (k,1)-Pascal triangle, which suggested this choice for the gnomonic numbers.
Schläfli-Poincaré (convex) polytope formula
Schläfli-Poincaré generalization of the Descartes-Euler (convex) polyhedral formula.[1]
For 1-dimensional (d = 1) regular convex polytopes:
where N0 is the number of 0-dimensional elements (vertices V) of the 1-dimensional (d = 1) regular convex polytope, which is always 2.
Recurrence equation
with initial conditions
where
Generating function
where
Order of basis
The order of basis of centered gnomonic numbers is:
where
The order of basis g for numbers of the form is k, since to represent the numbers in the congruence classes by adding numbers congruent to we need as many terms as the class number, for each congruence classes, e.g. for :
- numbers of form are expressible as 1 term of the form ;
- numbers of form are expressible as the sum of 2 terms of the form ;
- numbers of form are expressible as the sum of 3 terms of the form ;
- numbers of form are expressible as the sum of 4 terms of the form ;
- numbers of form are expressible as the sum of 5 terms of the form .
In 1638, Fermat proposed that every positive integer is a sum of at most three triangular numbers, four square numbers, five pentagonal numbers, and k k-polygonal numbers. Fermat claimed to have a proof of this result, although Fermat's proof has never been found. Joseph Louis Lagrange proved the square case (known as the four squares theorem[2]) in 1770 and Gauss proved the triangular case in 1796. In 1813, Cauchy finally proved the horizontal generalization that every nonnegative integer can be written as a sum of k k-gon numbers (known as the polygonal number theorem,[2]) while a vertical (higher dimensional) generalization has also been made (known as the Hilbert-Waring problem.)
A nonempty subset A of nonnegative integers is called a basis of order g if g is the minimum number with the property that every nonnegative integer can be written as a sum of g elements in A. Lagrange’s sum of four squares can be restated as the set of nonnegative squares forms a basis of order 4.
Theorem (Cauchy) For every , the set of k-gon numbers forms a basis of order k, i.e. every nonnegative integer can be written as a sum of k k-gon numbers.
We note that polygonal numbers are two dimensional analogues of squares. Obviously, cubes, fourth powers, fifth powers, ... are higher dimensional analogues of squares. In 1770, Waring stated without proof that every nonnegative integer can be written as a sum of 4 squares, 9 cubes, 19 fourth powers, and so on. In 1909, Hilbert proved that there is a finite number such that every nonnegative integer is a sum of th powers, i.e. the set of th powers forms a basis of order . The Hilbert-Waring problem[3] is concerned with the study of for . This problem was one of the most important research topics in additive number theory in last 90 years, and it is still a very active area of research.
In 1997, Conway et al. proved a theorem, called the fifteen theorem,[4] which states that, if a positive definite quadratic form with integer matrix entries represents all natural numbers up to 15, then it represents all natural numbers. This theorem contains Lagrange's four-square theorem, since every number up to 15 is the sum of at most four squares.
Differences
where
Partial sums
where
Partial sums of reciprocals
where
Sum of reciprocals
where
The infinite series diverges logarithmically, i.e.:
- as
Table of formulae and values
B | Name | Formulae
|
n = 0 | 1 | 2 | 3 | 4 | 5 | 6 | 7 | 8 | 9 | 10 | 11 | 12 | OEIS
number |
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
2 | 1 | 3 | 5 | 7 | 9 | 11 | 13 | 15 | 17 | 19 | 21 | 23 | 25 | A005408(n) | ||
3 | 1 | 3 | 5 | 7 | 9 | 11 | 13 | 15 | 17 | 19 | 21 | 23 | 25 | A005408(n) | ||
4 | 1 | 5 | 11 | 17 | 23 | 29 | 35 | 41 | 47 | 53 | 59 | 65 | 71 | A101328(n+2) | ||
5 | 1 | 5 | 9 | 13 | 17 | 21 | 25 | 29 | 33 | 37 | 41 | 45 | 49 | A016813(n) | ||
6 | 1 | 7 | 17 | 27 | 37 | 47 | 57 | 67 | 77 | 87 | 97 | 107 | 117 | A160912(n+1) | ||
7 | 1 | 7 | 13 | 19 | 25 | 31 | 37 | 43 | 49 | 55 | 61 | 67 | 73 | A016921(n) | ||
8 | 1 | 9 | 23 | 37 | 51 | 65 | 79 | 93 | 107 | 121 | 135 | 149 | 163 | Axxxxxx | ||
9 | 1 | 9 | 17 | 25 | 33 | 41 | 49 | 57 | 65 | 73 | 81 | 89 | 97 | A017077(n) | ||
10 | 1 | 11 | 29 | 47 | 65 | 83 | 101 | 119 | 137 | 155 | 173 | 191 | 209 | Axxxxxx | ||
11 | 1 | 11 | 21 | 31 | 41 | 51 | 61 | 71 | 81 | 91 | 101 | 111 | 121 | A017281(n) | ||
12 | 1 | 13 | 35 | 57 | 79 | 101 | 123 | 145 | 167 | 189 | 211 | 233 | 255 | Axxxxxx | ||
13 | 1 | 13 | 25 | 37 | 49 | 61 | 73 | 85 | 97 | 109 | 121 | 133 | 145 | A017533(n) | ||
14 | 1 | 15 | 41 | 67 | 93 | 119 | 145 | 171 | 197 | 223 | 249 | 275 | 301 | Axxxxxx | ||
15 | 1 | 15 | 29 | 43 | 57 | 71 | 85 | 99 | 113 | 127 | 141 | 155 | 169 | Axxxxxx | ||
16 | 1 | 17 | 47 | 77 | 107 | 137 | 167 | 197 | 227 | 257 | 287 | 317 | 347 | Axxxxxx | ||
17 | 1 | 17 | 33 | 49 | 65 | 81 | 97 | 113 | 129 | 145 | 161 | 177 | 193 | Axxxxxx | ||
18 | 1 | 19 | 53 | 87 | 121 | 155 | 189 | 223 | 257 | 291 | 325 | 359 | 393 | Axxxxxx | ||
19 | 1 | 19 | 37 | 55 | 73 | 91 | 109 | 127 | 145 | 163 | 181 | 199 | 217 | Axxxxxx | ||
20 | 1 | 21 | 59 | 97 | 135 | 173 | 211 | 249 | 287 | 325 | 363 | 401 | 439 | Axxxxxx | ||
21 | 1 | 21 | 41 | 61 | 81 | 101 | 121 | 141 | 161 | 181 | 201 | 221 | 241 | Axxxxxx | ||
22 | 1 | 23 | 65 | 107 | 149 | 191 | 233 | 275 | 317 | 359 | 401 | 443 | 485 | Axxxxxx | ||
23 | 1 | 23 | 45 | 67 | 89 | 111 | 133 | 155 | 177 | 199 | 221 | 243 | 265 | Axxxxxx | ||
24 | 1 | 25 | 71 | 117 | 163 | 209 | 255 | 301 | 347 | 393 | 439 | 485 | 531 | Axxxxxx | ||
25 | 1 | 25 | 49 | 73 | 97 | 121 | 145 | 169 | 193 | 217 | 241 | 265 | 289 | Axxxxxx | ||
26 | 1 | 27 | 77 | 127 | 177 | 227 | 277 | 327 | 377 | 427 | 477 | 527 | 577 | Axxxxxx | ||
27 | 1 | 27 | 53 | 79 | 105 | 131 | 157 | 183 | 209 | 235 | 261 | 287 | 313 | Axxxxxx | ||
28 | 1 | 29 | 83 | 137 | 191 | 245 | 299 | 353 | 407 | 461 | 515 | 569 | 623 | Axxxxxx | ||
29 | 1 | 29 | 57 | 85 | 113 | 141 | 169 | 197 | 225 | 253 | 281 | 309 | 337 | Axxxxxx |
B | Name | Generating
function
|
Order
of basis[2]
|
Differences
|
Partial sums
|
Partial sums of reciprocals
|
Sums of reciprocals
|
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2 |
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[5]
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3 |
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[5]
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4 | |||||||
5 |
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6 | |||||||
7 |
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8 | |||||||
9 |
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10 | |||||||
11 |
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12 | |||||||
13 |
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14 | |||||||
15 |
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17 |
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18 | |||||||
19 |
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20 | |||||||
21 |
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23 |
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Table of sequences
B | sequences |
---|---|
2 | {1, 3, 5, 7, 9, 11, 13, 15, 17, 19, 21, 23, 25, 27, 29, 31, 33, 35, 37, 39, 41, 43, 45, 47, 49, 51, 53, 55, 57, 59, 61, 63, 65, 67, 69, 71, 73, 75, 77, 79, 81, 83, 85, ...} |
3 | {1, 3, 5, 7, 9, 11, 13, 15, 17, 19, 21, 23, 25, 27, 29, 31, 33, 35, 37, 39, 41, 43, 45, 47, 49, 51, 53, 55, 57, 59, 61, 63, 65, 67, 69, 71, 73, 75, 77, 79, 81, 83, 85, ...} |
4 | {1, 5, 11, 17, 23, 29, 35, 41, 47, 53, 59, 65, 71, 77, 83, 89, 95, 101, 107, 113, 119, 125, 131, 137, 143, 149, 155, 161, 167, 173, 179, 185, 191, 197, 203, 209, ...} |
5 | {1, 5, 9, 13, 17, 21, 25, 29, 33, 37, 41, 45, 49, 53, 57, 61, 65, 69, 73, 77, 81, 85, 89, 93, 97, 101, 105, 109, 113, 117, 121, 125, 129, 133, 137, 141, 145, 149, ...} |
6 | {1, 7, 17, 27, 37, 47, 57, 67, 77, 87, 97, 107, 117, 127, 137, 147, 157, 167, 177, 187, 197, 207, 217, 227, 237, 247, 257, 267, 277, 287, 297, 307, 317, 327, 337, ...} |
7 | {1, 7, 13, 19, 25, 31, 37, 43, 49, 55, 61, 67, 73, 79, 85, 91, 97, 103, 109, 115, 121, 127, 133, 139, 145, 151, 157, 163, 169, 175, 181, 187, 193, 199, 205, 211, ...} |
8 | {1, 9, 23, 37, 51, 65, 79, 93, 107, 121, 135, 149, 163, 177, 191, 205, 219, 233, 247, 261, 275, 289, 303, 317, 331, 345, 359, 373, 387, 401, 415, 429, 443, 457, 471, ...} |
9 | {1, 9, 17, 25, 33, 41, 49, 57, 65, 73, 81, 89, 97, 105, 113, 121, 129, 137, 145, 153, 161, 169, 177, 185, 193, 201, 209, 217, 225, 233, 241, 249, 257, 265, 273, 281, ...} |
10 | {1, 11, 29, 47, 65, 83, 101, 119, 137, 155, 173, 191, 209, 227, 245, 263, 281, 299, 317, 335, 353, 371, 389, 407, 425, 443, 461, 479, 497, 515, 533, 551, 569, 587, 605, ...} |
11 | {1, 11, 21, 31, 41, 51, 61, 71, 81, 91, 101, 111, 121, 131, 141, 151, 161, 171, 181, 191, 201, 211, 221, 231, 241, 251, 261, 271, 281, 291, 301, 311, 321, 331, 341, ...} |
12 | {1, 13, 35, 57, 79, 101, 123, 145, 167, 189, 211, 233, 255, 277, 299, 321, 343, 365, 387, 409, 431, 453, 475, 497, 519, 541, 563, 585, 607, 629, 651, 673, 695, 717, ...} |
13 | {1, 13, 25, 37, 49, 61, 73, 85, 97, 109, 121, 133, 145, 157, 169, 181, 193, 205, 217, 229, 241, 253, 265, 277, 289, 301, 313, 325, 337, 349, 361, 373, 385, 397, 409, ...} |
14 | {1, 15, 41, 67, 93, 119, 145, 171, 197, 223, 249, 275, 301, 327, 353, 379, 405, 431, 457, 483, 509, 535, 561, 587, 613, 639, 665, 691, 717, 743, 769, 795, 821, ...} |
15 | {1, 15, 29, 43, 57, 71, 85, 99, 113, 127, 141, 155, 169, 183, 197, 211, 225, 239, 253, 267, 281, 295, 309, 323, 337, 351, 365, 379, 393, 407, 421, 435, 449, 463, ...} |
16 | {1, 17, 47, 77, 107, 137, 167, 197, 227, 257, 287, 317, 347, 377, 407, 437, 467, 497, 527, 557, 587, 617, 647, 677, 707, 737, 767, 797, 827, 857, 887, 917, 947, ...} |
17 | {1, 17, 33, 49, 65, 81, 97, 113, 129, 145, 161, 177, 193, 209, 225, 241, 257, 273, 289, 305, 321, 337, 353, 369, 385, 401, 417, 433, 449, 465, 481, 497, 513, 529, ...} |
18 | {1, 19, 53, 87, 121, 155, 189, 223, 257, 291, 325, 359, 393, 427, 461, 495, 529, 563, 597, 631, 665, 699, 733, 767, 801, 835, 869, 903, 937, 971, 1005, 1039, 1073, ...} |
19 | {1, 19, 37, 55, 73, 91, 109, 127, 145, 163, 181, 199, 217, 235, 253, 271, 289, 307, 325, 343, 361, 379, 397, 415, 433, 451, 469, 487, 505, 523, 541, 559, 577, 595, ...} |
20 | {1, 21, 59, 97, 135, 173, 211, 249, 287, 325, 363, 401, 439, 477, 515, 553, 591, 629, 667, 705, 743, 781, 819, 857, 895, 933, 971, 1009, 1047, 1085, 1123, 1161, ...} |
21 | {1, 21, 41, 61, 81, 101, 121, 141, 161, 181, 201, 221, 241, 261, 281, 301, 321, 341, 361, 381, 401, 421, 441, 461, 481, 501, 521, 541, 561, 581, 601, 621, 641, 661, ...} |
22 | {1, 23, 65, 107, 149, 191, 233, 275, 317, 359, 401, 443, 485, 527, 569, 611, 653, 695, 737, 779, 821, 863, 905, 947, 989, 1031, 1073, 1115, 1157, 1199, 1241, 1283, ...} |
23 | {1, 23, 45, 67, 89, 111, 133, 155, 177, 199, 221, 243, 265, 287, 309, 331, 353, 375, 397, 419, 441, 463, 485, 507, 529, 551, 573, 595, 617, 639, 661, 683, 705, 727, ...} |
24 | {1, 25, 71, 117, 163, 209, 255, 301, 347, 393, 439, 485, 531, 577, 623, 669, 715, 761, 807, 853, 899, 945, 991, 1037, 1083, 1129, 1175, 1221, 1267, 1313, 1359, 1405, ...} |
25 | {1, 25, 49, 73, 97, 121, 145, 169, 193, 217, 241, 265, 289, 313, 337, 361, 385, 409, 433, 457, 481, 505, 529, 553, 577, 601, 625, 649, 673, 697, 721, 745, 769, 793, ...} |
26 | {1, 27, 77, 127, 177, 227, 277, 327, 377, 427, 477, 527, 577, 627, 677, 727, 777, 827, 877, 927, 977, 1027, 1077, 1127, 1177, 1227, 1277, 1327, 1377, 1427, 1477, ...} |
27 | {1, 27, 53, 79, 105, 131, 157, 183, 209, 235, 261, 287, 313, 339, 365, 391, 417, 443, 469, 495, 521, 547, 573, 599, 625, 651, 677, 703, 729, 755, 781, 807, 833, 859, ...} |
28 | {1, 29, 83, 137, 191, 245, 299, 353, 407, 461, 515, 569, 623, 677, 731, 785, 839, 893, 947, 1001, 1055, 1109, 1163, 1217, 1271, 1325, 1379, 1433, 1487, 1541, 1595, ...} |
29 | {1, 29, 57, 85, 113, 141, 169, 197, 225, 253, 281, 309, 337, 365, 393, 421, 449, 477, 505, 533, 561, 589, 617, 645, 673, 701, 729, 757, 785, 813, 841, 869, 897, 925, ...} |
See also
Notes
- ↑ Weisstein, Eric W., Polyhedral Formula, from MathWorld—A Wolfram Web Resource..
- ↑ 2.0 2.1 2.2 Weisstein, Eric W., Lagrange's Four-Square Theorem, from MathWorld—A Wolfram Web Resource.. Cite error: Invalid
<ref>
tag; name "FermatsPolygonalNumberTheorem" defined multiple times with different content - ↑ Weisstein, Eric W., Waring's Problem, from MathWorld—A Wolfram Web Resource..
- ↑ Weisstein, Eric W., Fifteen Theorem, from MathWorld—A Wolfram Web Resource..
- ↑ 5.0 5.1 Weisstein, Eric W., Digamma Function, from MathWorld—A Wolfram Web Resource.. Cite error: Invalid
<ref>
tag; name "DigammaFunction" defined multiple times with different content - ↑ 6.0 6.1 Weisstein, Eric W., Euler-Mascheroni Constant, from MathWorld—A Wolfram Web Resource..
External links
- S. Plouffe, Approximations de Séries Génératrices et Quelques Conjectures, Dissertation, Université du Québec à Montréal, 1992.
- S. Plouffe, 1031 Generating Functions and Conjectures, Université du Québec à Montréal, 1992.
- Herbert S. Wilf, generatingfunctionology, 2nd ed., 1994.