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A009987
Powers of 43.
10
1, 43, 1849, 79507, 3418801, 147008443, 6321363049, 271818611107, 11688200277601, 502592611936843, 21611482313284249, 929293739471222707, 39959630797262576401, 1718264124282290785243, 73885357344138503765449
OFFSET
0,2
COMMENTS
Same as Pisot sequences E(1, 43), L(1, 43), P(1, 43), T(1, 43). Essentially same as Pisot sequences E(43, 1849), L(43, 1849), P(43, 1849), T(43, 1849). 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 43-colored compositions of n such that no adjacent parts have the same color. - Milan Janjic, Nov 17 2011
Numbers n such that sigma(43*n) = 43*n + sigma(n). - Jahangeer Kholdi, Nov 24 2013
FORMULA
G.f.: 1/(1-43*x). - Philippe Deléham, Nov 24 2008
a(n) = 43^n; a(n) = 43*a(n-1), a(0)=1. - Vincenzo Librandi, Nov 21 2010
MATHEMATICA
43^Range[0, 20] (* Harvey P. Dale, Nov 30 2014 *)
PROG
(Magma)[43^n: n in [0..20]] // Vincenzo Librandi, Nov 21 2010
(PARI) a(n)=43^n \\ Charles R Greathouse IV, Oct 07 2015
CROSSREFS
Sequence in context: A218745 A331777 A262470 * A267532 A335207 A076572
KEYWORD
nonn,easy
AUTHOR
STATUS
approved