A009982 Powers of 38.

1, 38, 1444, 54872, 2085136, 79235168, 3010936384, 114415582592, 4347792138496, 165216101262848, 6278211847988224, 238572050223552512, 9065737908494995456, 344498040522809827328, 13090925539866773438464, 497455170514937390661632, 18903296479567620845142016

Offset: 0

Author

N. J. A. Sloane

Keywords

• nonn
• easy

Comments

Same as Pisot sequences E(1, 38), L(1, 38), P(1, 38), T(1, 38). Essentially same as Pisot sequences E(38, 1444), L(38, 1444), P(38, 1444), T(38, 1444). See A008776 for definitions of Pisot sequences.

The compositions of n in which each natural number is colored by one of p different colors are called p-colored compositions of n. For n >= 1, a(n) equals the number of 38-colored compositions of n such that no adjacent parts have the same color. - Milan Janjic, Nov 17 2011. [See A000244 for a proof.]

Links

• T. D. Noe, Table of n, a(n) for n=0..100
• Tanya Khovanova, Recursive Sequences.
• Index entries for linear recurrences with constant coefficients, signature (38).

Crossrefs

Cf. A000079, A000244, A001029, A008776.

Programs

Magma

[38^n: n in [0..20]]; // Vincenzo Librandi, Nov 21 2010

Mathematica

38^Range[0, 19] (* Alonso del Arte, Feb 18 2017 *)

PARI

a(n)=38^n \\ M. F. Hasler, Feb 21 2017

Formula

G.f.: 1/(1 - 38*x). - Philippe Deléham, Nov 24 2008

a(n) = 38^n; a(n) = 38*a(n-1), n > 0, a(0) = 1. - Vincenzo Librandi, Nov 21 2010

From Elmo R. Oliveira, Jul 10 2025: (Start)

E.g.f.: exp(38*x).

a(n) = A000079(n)*A001029(n). (End)