OFFSET
1,3
COMMENTS
Multiplicative. See A030205 for formula. - Andrew Howroyd, Aug 05 2018
LINKS
Seiichi Manyama, Table of n, a(n) for n = 1..1000
Yves Martin and Ken Ono, Eta-Quotients and Elliptic Curves, Proc. Amer. Math. Soc. 125, No 11 (1997), 3169-3176.
FORMULA
a(2n-1) = A030205(n-1), a(2n) = 0 for n > 0.
G.f.: (eta(x^2) * eta(x^10))^2. - Andrew Howroyd, Aug 05 2018
Euler transform of period 10 sequence [0, -2, 0, -2, 0, -2, 0, -2, 0, -4, ...]. - Georg Fischer, Nov 17 2022
MATHEMATICA
QPochhammer[x^2]^2*QPochhammer[x^10]^2 + O[x]^100 // CoefficientList[#, x]& (* Jean-François Alcover, Sep 19 2019 *)
PROG
(PARI) seq(n)={Vec((eta(x^2 + O(x*x^n)) * eta(x^10 + O(x*x^n)))^2)} \\ Andrew Howroyd, Aug 05 2018
CROSSREFS
KEYWORD
sign,mult
AUTHOR
Seiichi Manyama, Sep 10 2016
STATUS
approved