A370798 Expansion of (1/x) * Series_Reversion( x/(x+1/(1-x-x^4)) ).
1, 2, 5, 15, 52, 200, 824, 3549, 15745, 71343, 328537, 1532838, 7230341, 34425026, 165230211, 798643501, 3884110353, 18993027790, 93325418867, 460562269745, 2281769792691, 11344607718373, 56585135577335, 283067227288767, 1419859530338142, 7139644680794750
Offset: 0
Keywords
Programs
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PARI
my(N=30, x='x+O('x^N)); Vec(serreverse(x/(x+1/(1-x-x^4)))/x)
Formula
a(n) = Sum_{k=0..n} binomial(n,k) * b(k), where g.f. B(x) = Sum_{k>=0} b(k)*x^k satisfies B(x) = (1/x) * Series_Reversion( x*(1-x-x^4) ).