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A001029 Powers of 19.
(Formerly M5079 N2198)
8
1, 19, 361, 6859, 130321, 2476099, 47045881, 893871739, 16983563041, 322687697779, 6131066257801, 116490258898219, 2213314919066161, 42052983462257059, 799006685782884121, 15181127029874798299, 288441413567621167681, 5480386857784802185939, 104127350297911241532841, 1978419655660313589123979, 37589973457545958193355601 (list; graph; refs; listen; history; 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 19-colored compositions of n such that no adjacent parts have the same color. - Milan Janjic, Nov 17 2011

REFERENCES

N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 (includes this sequence).

N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

LINKS

T. D. Noe, Table of n, a(n) for n=0..100

P. J. Cameron, Sequences realized by oligomorphic permutation groups, J. Integ. Seqs. Vol. 3 (2000), #00.1.5.

INRIA Algorithms Project, Encyclopedia of Combinatorial Structures 283

Tanya Khovanova, Recursive Sequences

S. Plouffe, Approximations de S\'{e}ries G\'{e}n\'{e}ratrices et Quelques Conjectures, Dissertation, Universit\'{e} du Qu\'{e}bec \`{a} Montr\'{e}al, 1992.

S. Plouffe, 1031 Generating Functions and Conjectures, Universit\'{e} du Qu\'{e}bec \`{a} Montr\'{e}al, 1992.

Y. Puri and T. Ward, Arithmetic and growth of periodic orbits, J. Integer Seqs., Vol. 4 (2001), #01.2.1.

FORMULA

G.f.: 1/(1-19x), e.g.f.: exp(19x)

a(n) = 19^n; a(n) = 19*a(n-1) with a(0)=1. [From Vincenzo Librandi, Nov 21 2010]

MAPLE

A001029:=-1/(-1+19*z); [Conjectured by S. Plouffe in his 1992 dissertation.]

MATHEMATICA

Table[19^n, {n, 0, 40}] (*From Vladimir Joseph Stephan Orlovsky, Feb 15 2011*)

PROG

(Other) sage: [lucas_number1(n, 19, 0) for n in xrange(1, 17)]# [From Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), Apr 29 2009]

(MAGMA) [ 19^n: n in [0..20] ]; [From Vincenzo Librandi, Nov 21 2010]

(MAGMA) [ n eq 1 select 1 else 19*Self(n-1): n in [1..21] ];

CROSSREFS

Sequence in context: A171293 A045609 A128360 * A057685 A041686 A023283

Adjacent sequences:  A001026 A001027 A001028 * A001030 A001031 A001032

KEYWORD

nonn

AUTHOR

N. J. A. Sloane (njas(AT)research.att.com).

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Last modified February 17 16:35 EST 2012. Contains 206054 sequences.