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A107448 Triangular form sequence made from a version of A082605 Euler extension. 1
5, 7, 11, 17, 13, 17, 23, 31, 41, 53, 67, 83, 101, 19, 23, 29, 37, 47, 59, 73, 89, 107, 127, 149, 173, 199, 227, 257, 43, 47, 53, 61, 71, 83, 97, 113, 131, 151, 173, 197, 223, 251, 281, 313, 347, 383, 421, 461, 503, 547, 593, 641, 691, 743, 797, 853, 911, 971, 1033 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

REFERENCES

Advanced Number Theory, Harvey Cohn, Dover Books, 1963, Page 155

LINKS

Table of n, a(n) for n=0..58.

FORMULA

b[m]=Abs[1-4*b[m-2]]-2 a(n, m) = n^2+n+b[m]

EXAMPLE

{5},

{7, 11, 17},

{13, 17, 23, 31, 41, 53, 67, 83, 101},

{19, 23, 29, 37, 47, 59, 73, 89, 107, 127, 149, 173, 199, 227, 257},

{43, 47, 53, 61, 71, 83, 97, 113, 131, 151, 173, 197, 223, 251, 281, 313,

347, 383, 421, 461, 503, 547, 593, 641, 691, 743, 797, 853, 911, 971, 1033,

1097, 1163, 1231, 1301, 1373, 1447, 1523, 1601},

{67, 71, 77, 85, 95, 107, 121, 137, 155, 175, 197, 221, 247, 275, 305, 337,

371, 407, 445, 485, 527, 571, 617, 665, 715, 767, 821, 877, 935, 995, 1057,

1121, 1187, 1255, 1325, 1397, 1471, 1547, 1625, 1705, 1787, 1871, 1957, 2045,

2135, 2227, 2321, 2417, 2515, 2615, 2717, 2821, 2927, 3035, 3145, 3257, 3371,

3487, 3605, 3725, 3847, 3971, 4097}

MATHEMATICA

a[1] = 3; a[2] = 5; a[3] = 11; a[n_] := a[n] = Abs[1 - 4*a[n - 2]] - 2; euler = Table[a[n], {n, 1, 10}] a0 = Table[Table[x^2 + x + euler[[i]], {x, 1, euler[[i]] - 2}], {i, 1, 7}] MatrixForm[a0] b = Flatten[a0]

CROSSREFS

Cf. A082605.

Sequence in context: A072055 A314300 A189320 * A147853 A111226 A168224

Adjacent sequences:  A107445 A107446 A107447 * A107449 A107450 A107451

KEYWORD

nonn,uned

AUTHOR

Roger L. Bagula, May 26 2005

STATUS

approved

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Last modified December 3 21:17 EST 2021. Contains 349468 sequences. (Running on oeis4.)