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A093949
Expansion of (q^5/12)eta(q^3)^5/eta(q) in powers of q.
0
1, 1, 2, -2, 0, -3, 1, -5, -3, 0, 2, 1, -3, 1, 5, 0, 5, 5, 2, 0, -5, 11, -3, -2, 0, 6, 0, -7, -13, 0, -3, 5, 0, -10, 0, -1, -6, 0, -7, 5, -7, 6, 7, -3, 0, 9, 10, -7, 0, 0, 1, 9, 5, 6, 0, 0, 19, -10, 11, 0, -6, -10, -7, -2, 10, 9, 0, -2, -11, 0, -11, -11, 15, -7, 0, -11, -6, -20, 0, 0, 9, 0, -3, 0, 0, -5, 5, -2, 1, -10, -7, 14, 0, -11
OFFSET
1,3
COMMENTS
Euler transform of period 3 sequence [1,1,-4,...].
a(25n-10)=5a(n). a(5n)=0 unless n == 3 (mod 5).
FORMULA
G.f.: x Product_{k>0} (1-x^(3k))^5/(1-x^k).
PROG
(PARI) a(n)=local(X); if(n<1, 0, X=x+x*O(x^n); n--; polcoeff(eta(X^3)^5/eta(X), n))
CROSSREFS
Sequence in context: A071427 A248813 A235917 * A324518 A108807 A129236
KEYWORD
sign
AUTHOR
Michael Somos, Apr 18 2004
STATUS
approved