OFFSET
1,5
COMMENTS
The bisection of this sequence containing all nonzero terms is A030188.
Multiplicative. See A030188 for formula. - Andrew Howroyd, Jul 31 2018
LINKS
Seiichi Manyama, Table of n, a(n) for n = 1..10000
Yves Martin and Ken Ono, Eta-Quotients and Elliptic Curves, Proc. Amer. Math. Soc. 125, No 11 (1997), 3169-3176.
FORMULA
G.f.: x * Product_{k>0} (1 - x^(2*k)) * (1 - x^(4*k)) * (1 - x^(6*k)) * (1 - x^(12*k)).
a(2*n+1) = A030188(n). - Michel Marcus, Sep 25 2016
Euler transform of period 12 sequence [0, -1, 0, -2, 0, -2, 0, -2, 0, -1, 0, -4, ...]. - Georg Fischer, Nov 17 2022
MATHEMATICA
CoefficientList[Series[QPochhammer[x^2] QPochhammer[x^4] QPochhammer[x^6] QPochhammer[x^12], {x, 0, 100}], x] (* Jan Mangaldan, Jan 04 2017 *)
CROSSREFS
KEYWORD
sign,mult
AUTHOR
Seiichi Manyama, Sep 22 2016
STATUS
approved