The On-Line Encyclopedia of Integer Sequences (OEIS)

Revision History for A349035

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A349035

G.f. A(x) satisfies: A(x) = 1 / (1 - x - x^2 * A(-2*x)).
(history; published version)

#6 by Susanna Cuyler at Sat Nov 06 20:15:40 EDT 2021

STATUS

reviewed

approved

#5 by Joerg Arndt at Sat Nov 06 12:05:22 EDT 2021

STATUS

proposed

reviewed

#4 by Ilya Gutkovskiy at Sat Nov 06 11:36:52 EDT 2021

STATUS

editing

proposed

#3 by Ilya Gutkovskiy at Sat Nov 06 10:57:49 EDT 2021

CROSSREFS

Cf. A001006, A015097, A348878, A349036, A349037.

#2 by Ilya Gutkovskiy at Sat Nov 06 10:51:56 EDT 2021

NAME

allocated for Ilya Gutkovskiy

G.f. A(x) satisfies: A(x) = 1 / (1 - x - x^2 * A(-2*x)).

DATA

1, 1, 2, 1, 9, 6, 165, 97, 10970, 8617, 2838793, 1206206, 2912348749, 3338391105, 11938619074866, -3485058191151, 195607339607544393, 505337929567029942, 12820529140255160177781, -40595263531274884237983, 3360756421633193695872693450

OFFSET

0,3

FORMULA

a(0) = 1; a(n) = a(n-1) + Sum_{k=0..n-2} (-2)^k * a(k) * a(n-k-2).

MATHEMATICA

nmax = 20; A[_] = 0; Do[A[x_] = 1/(1 - x - x^2 A[-2 x]) + O[x]^(nmax + 1) // Normal, nmax + 1]; CoefficientList[A[x], x]

a[0] = 1; a[n_] := a[n] = a[n - 1] + Sum[(-2)^k a[k] a[n - k - 2], {k, 0, n - 2}]; Table[a[n], {n, 0, 20}]

CROSSREFS

Cf. A001006, A015097, A348878.

KEYWORD

allocated

sign

AUTHOR

Ilya Gutkovskiy, Nov 06 2021

STATUS

approved

editing

#1 by Ilya Gutkovskiy at Sat Nov 06 10:51:56 EDT 2021

NAME

allocated for Ilya Gutkovskiy

KEYWORD

allocated

STATUS

approved