A360898 G.f. satisfies A(x) = 1 + x/(1 + x^3) * A(x/(1 + x^3)).
1, 1, 1, 1, 0, -2, -5, -8, -5, 13, 57, 117, 110, -179, -1089, -2591, -2852, 4370, 30383, 77884, 88638, -165233, -1133248, -2963659, -3172087, 8519500, 53092522, 135857134, 122296383, -543728791, -2983007603, -7219203443, -4427302115, 40439842811, 194091075002
Offset: 0
Keywords
Links
- Seiichi Manyama, Table of n, a(n) for n = 0..1000
Programs
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PARI
a_vector(n) = my(v=vector(n+1)); v[1]=1; for(i=1, n, v[i+1]=sum(j=0, (i-1)\3, (-1)^j*binomial(i-1-2*j, j)*v[i-3*j])); v;
Formula
a(0) = 1; a(n) = Sum_{k=0..floor((n-1)/3)} (-1)^k * binomial(n-1-2*k,k) * a(n-1-3*k).