OFFSET
0,7
LINKS
Paul D. Hanna, Table of n, a(n) for n = 0..10000
EXAMPLE
G.f.: A(x) = 1 + x + x^2 + x^4 - x^5 + 2*x^6 + x^8 - 2*x^9 + 4*x^10 - x^11 + x^12 - x^13 + 2*x^14 + x^16 - 3*x^17 + 7*x^18 - 4*x^19 + 2*x^20 +...
where
A(x) = 1 + x + x^2*(1-x) + x^3 + x^4*(1-x)^2 + x^5 + x^6*(1-x) + x^7 + x^8*(1-x)^3 + x^9 + x^10*(1-x) + x^11 + x^12*(1-x)^2 + x^13 + x^14*(1-x) + x^16*(1-x)^4 +...
PROG
(PARI) {a(n)=polcoeff(1+sum(m=1, n, x^m*(1-x+x*O(x^n))^valuation(m, 2)), n)}
for(n=0, 128, print1(a(n), ", "))
CROSSREFS
KEYWORD
sign
AUTHOR
Paul D. Hanna, Jul 06 2013
STATUS
approved