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A285245
Expansion of Product_{k>=1} 1/(1 - k*x^(k^2)).
5
1, 1, 1, 1, 3, 3, 3, 3, 7, 10, 10, 10, 18, 24, 24, 24, 44, 56, 65, 65, 105, 129, 147, 147, 227, 292, 328, 355, 515, 645, 717, 771, 1107, 1367, 1562, 1670, 2429, 2949, 3339, 3555, 5073, 6181, 6961, 7546, 10582, 13059, 14619, 15789, 21925, 26886, 30235, 32575
OFFSET
0,5
LINKS
FORMULA
a(n) ~ c * 2^(n/4), where
c = 6.362854320457366874306510139107365081972383711876544726... if mod(n,4)=0
c = 6.470997903106304472752360748461108347899808941622559468... if mod(n,4)=1
c = 6.154059402265470959096395812318265046714869376472639022... if mod(n,4)=2
c = 5.624747659153211728892605407048217108787120474872434485... if mod(n,4)=3
MATHEMATICA
nmax = 100; CoefficientList[Series[Product[1/(1 - k*x^(k^2)), {k, 1, nmax}], {x, 0, nmax}], x]
CROSSREFS
KEYWORD
nonn
AUTHOR
Vaclav Kotesovec, Apr 15 2017
STATUS
approved