

A346076


a(n) = 1 + Sum_{k=1..n4} a(k) * a(nk4).


2



1, 1, 1, 1, 1, 2, 3, 4, 5, 7, 11, 17, 25, 36, 54, 84, 131, 201, 307, 475, 745, 1172, 1837, 2878, 4531, 7173, 11381, 18057, 28669, 45624, 72796, 116336, 186066, 297865, 477505, 766621, 1232214, 1982292, 3191693, 5143974, 8298640, 13399691, 21652705, 35014373, 56663700
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OFFSET

0,6


LINKS

Table of n, a(n) for n=0..44.


FORMULA

G.f. A(x) satisfies: A(x) = 1 / (1  x) + x^4 * A(x) * (A(x)  1).


MATHEMATICA

a[n_] := a[n] = 1 + Sum[a[k] a[n  k  4], {k, 1, n  4}]; Table[a[n], {n, 0, 44}]
nmax = 44; A[_] = 0; Do[A[x_] = 1/(1  x) + x^4 A[x] (A[x]  1) + O[x]^(nmax + 1) // Normal, nmax + 1]; CoefficientList[A[x], x]


CROSSREFS

Cf. A105633, A217282, A307971, A343305, A346048, A346073, A346075, A346077.
Sequence in context: A245823 A143284 A343305 * A339357 A279065 A327325
Adjacent sequences: A346073 A346074 A346075 * A346077 A346078 A346079


KEYWORD

nonn


AUTHOR

Ilya Gutkovskiy, Jul 04 2021


STATUS

approved



