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A034436 Expansion of (eta(q) * eta(q^9))^12 in powers of q. 0
1, -12, 54, -88, -99, 540, -418, -648, 594, 824, 1200, -4752, 847, 5292, -7074, 9272, 1296, -11880, -10276, -8304, 69390, -14344, -59940, 34992, -82707, 35640, 108594, 77792, -12144, -440748, 106920, 303192, -86616, 397176, -158112, -589680, -372117, 302016 (list; graph; refs; listen; history; text; internal format)
OFFSET

5,2

LINKS

Table of n, a(n) for n=5..42.

FORMULA

Euler transform of period 9 sequence [ -12, -12, -12, -12, -12, -12, -12, -12, -24, ...]. - Michael Somos, Sep 21 2005

G.f.: x^5 * (Product_{k>0} (1 - x^k) * (1 - x^(9*k)))^12. - Michael Somos, Sep 21 2005

EXAMPLE

G.f. = q^5 - 12*q^6 + 54*q^7 - 88*q^8 - 99*q^9 + 540*q^10 - 418*q^11 + ...

MATHEMATICA

a[ n_] := SeriesCoefficient[ q^5 (QPochhammer[ q] QPochhammer[ q^9])^12, {q, 0, n}]; (* Michael Somos, Feb 22 2015 *)

PROG

(PARI) {a(n) = local(A); if( n<5, 0, n-=5; A = x *O(x^n); polcoeff( (eta(x + A) * eta(x^9 + A))^12, n))}; /* Michael Somos, Sep 21 2005 */

CROSSREFS

Sequence in context: A030182 A060171 A133078 * A186210 A209676 A000735

Adjacent sequences:  A034433 A034434 A034435 * A034437 A034438 A034439

KEYWORD

sign

AUTHOR

N. J. A. Sloane

STATUS

approved

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Last modified February 24 09:40 EST 2020. Contains 332209 sequences. (Running on oeis4.)