A091905 Expansion of (1-4*x)/((1+4*x)*(1-8*x)).

1, 0, 32, 128, 1536, 10240, 90112, 688128, 5636096, 44564480, 358612992, 2860515328, 22917677056, 183207198720, 1466194460672, 11727408201728, 93827855548416, 750588484648960, 6004845316145152, 48038212773347328, 384307901210034176, 3074454413587251200, 24595670493070098432

Offset

0,3

Links

Table of n, a(n) for n=0..22.

Index entries for linear recurrences with constant coefficients, signature (4,32).

Formula

a(n) = 8^n/3 + 2*(-4)^n/3 = 32*A091904(n-1).

a(n) = 4^n*A078008(n). - R. J. Mathar, Mar 08 2021

E.g.f.: (exp(8*x) + 2*exp(-4*x))/3. - Amiram Eldar, Feb 20 2026

Mathematica

LinearRecurrence[{4, 32}, {1, 0}, 23] (* Amiram Eldar, Feb 20 2026 *)

Crossrefs

Cf. A078008, A091904.

Sequence in context: A239728 A244082 A033323 * A100626 A330818 A231045

Adjacent sequences: A091902 A091903 A091904 * A091906 A091907 A091908

Keyword

easy,nonn

Author

Paul Barry, Feb 10 2004

Status

approved