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A274343 Irregular triangle read by rows giving the denominators of the coefficients of the Eisenstein series G_{2*n} multiplied by 2*n-1, for n >= 2. Also Laurent coefficients of Weierstrass's P function. 1
1, 1, 3, 11, 13, 39, 33, 2431, 663, 247, 2717, 80223, 1989, 1062347, 3187041, 16055, 6605027, 77571, 11685817, 1062347, 2002524095, 4405553009, 247, 2717, 497705, 155409680283, 11559397707, 1123416017295, 74894401153, 114727509, 5643476995, 409716429837, 10158258591, 909705199, 233400836858808047, 190964321066297493, 18394643943, 34825896536145, 229850917138557, 17096349208653, 357856262339147, 24291640943843637507, 602272089516784401, 174041631153 (list; graph; refs; listen; history; text; internal format)
OFFSET
2,3
COMMENTS
The length of row n is A008615(n), n >= 2.
The numerator triangle is given in A274342 where also details and references are given.
a(n) = denominator(r(n)) where the rationals r(n) are reduced to lowest terms obtained from the c(n) recurrence given in a comment of A274342 as coefficients of powers of c2 and c3 corresponding to the partitions of n with parts 2 and 3 only, when sorted with increasing number of parts.
LINKS
EXAMPLE
The irregular triangle a(n, m) begins:
n\m 1 2 3
2: 1
3: 1
4: 3
5: 11
6: 13 39
7: 33
8: 2431 663
9: 247 2717
10: 8022 1989
11: 1062347 3187041
12: 16055 6605027 77571
13: 11685817 1062347
14: 2002524095 4405553009 249951
15: 497705 155409680283 11559397707
16: 1123416017295 74894401153 114727509
17: 5643476995 409716429837 10158258591
...
row n = 18: 909705199 233400836858808047 190964321066297493 18394643943,
row n = 19: 34825896536145 229850917138557 17096349208653,
row n = 20: 357856262339147 24291640943843637507 602272089516784401 174041631153.
...
For the rationals r(n), n = 2..20, see A274342.
CROSSREFS
Cf. A274342.
Sequence in context: A119145 A168454 A181086 * A113049 A370425 A225097
KEYWORD
nonn,tabf,frac,easy
AUTHOR
Wolfdieter Lang, Jun 20 2016
STATUS
approved

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Last modified April 13 05:16 EDT 2024. Contains 371639 sequences. (Running on oeis4.)