OFFSET
0,36
COMMENTS
|a(n)| < 3 if n < 1299, a(1299) = 3.
FORMULA
G.f.: Product_{k>0} (1-x^(12k))^2 * (1-x^(12k-6)) / ((1-x^(12k-5))*(1-x^(12k-7))).
PROG
(PARI) a(n)=local(A); if(n<0, 0, A=1+x*O(x^n); polcoeff(prod(n=1, n\12+1, if(m=12*n, (A-x^m)^2*(A-x^(m-6))/(A-x^(m-5))/(A-x^(m-7)))), n))
CROSSREFS
KEYWORD
sign
AUTHOR
Michael Somos, May 10 2004
STATUS
approved