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A009984 Powers of 40. 2
1, 40, 1600, 64000, 2560000, 102400000, 4096000000, 163840000000, 6553600000000, 262144000000000, 10485760000000000, 419430400000000000, 16777216000000000000, 671088640000000000000, 26843545600000000000000 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

COMMENTS

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 40-colored compositions of n such that no adjacent parts have the same color. - Milan Janjic, Nov 17 2011

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 (40).

FORMULA

G.f.: 1/(1 - 40*x). - Philippe Deléham, Nov 24 2008

a(n) = 40^n; a(n) = 40*a(n-1) a(0) = 1. - Vincenzo Librandi, Nov 21 2010

MATHEMATICA

40^Range[0, 19] (* Alonso del Arte, Sep 04 2016 *)

PROG

(MAGMA) [40^n: n in [0..20]] // Vincenzo Librandi, Nov 21 2010

(PARI) a(n)=40^n \\ Charles R Greathouse IV, Jun 19 2015

(PARI) powers(40, 10) \\ Charles R Greathouse IV, Jun 19 2015

CROSSREFS

Cf. A000302 (powers of 4), A011557 (powers of 10).

Sequence in context: A207425 A207740 A208082 * A041761 A229635 A229584

Adjacent sequences:  A009981 A009982 A009983 * A009985 A009986 A009987

KEYWORD

nonn,easy

AUTHOR

N. J. A. Sloane, Dec 11 1996

STATUS

approved

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Last modified September 28 19:27 EDT 2016. Contains 276604 sequences.