Annual appeal: Please make a donation to keep the OEIS running! Over 6000 articles have referenced us, often saying "we discovered this result with the help of the OEIS". Other ways to donate

1,2

Table of n, a(n) for n=1..44.

Empirical g.f.: -x*(x^12 -2*x^11 +x^10 -2*x^9 +2*x^8 +2*x^6 -x^5 -x^3 +x^2 +x +1) / ((x -1)^3*(x^2 +1)*(x^2 +x +1)*(x^4 -x^2 +1)). - Colin Barker, Aug 16 2014

Sequence in context: A002815 A109512 A025205 * A004116 A004129 A219646

Adjacent sequences: A024187 A024188 A024189 * A024191 A024192 A024193

nonn

Clark Kimberling

approved