|
|
A291667
|
|
Expansion of Product_{k>=1} ((1 + x^(k^2)) / (1 - x^(k^2)))^k.
|
|
2
|
|
|
1, 2, 2, 2, 6, 10, 10, 10, 18, 32, 38, 38, 50, 86, 110, 110, 134, 206, 272, 290, 342, 466, 610, 682, 770, 1012, 1310, 1492, 1654, 2130, 2698, 3066, 3410, 4210, 5310, 6106, 6812, 8078, 10118, 11750, 13006, 15198, 18654, 21810, 24178, 28092, 33682, 39330, 43866
(list;
graph;
refs;
listen;
history;
text;
internal format)
|
|
|
OFFSET
|
0,2
|
|
COMMENTS
|
|
|
LINKS
|
|
|
FORMULA
|
log(a(n)) ~ Pi*sqrt(n/2).
|
|
MATHEMATICA
|
nmax = 60; CoefficientList[Series[Product[((1+x^(k^2))/(1-x^(k^2)))^k, {k, 1, nmax}], {x, 0, nmax}], x]
|
|
CROSSREFS
|
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
|
|
STATUS
|
approved
|
|
|
|