login
A009967
Powers of 23.
37
1, 23, 529, 12167, 279841, 6436343, 148035889, 3404825447, 78310985281, 1801152661463, 41426511213649, 952809757913927, 21914624432020321, 504036361936467383, 11592836324538749809, 266635235464391245607, 6132610415680998648961, 141050039560662968926103, 3244150909895248285300369, 74615470927590710561908487, 1716155831334586342923895201
OFFSET
0,2
COMMENTS
Same as Pisot sequences E(1, 23), L(1, 23), P(1, 23), T(1, 23). Essentially same as Pisot sequences E(23, 529), L(23, 529), P(23, 529), T(23, 529). 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 23-colored compositions of n such that no adjacent parts have the same color. - Milan Janjic, Nov 17 2011
Numbers n such that sigma(23*n) = 23*n + sigma(n). - Jahangeer Kholdi, Nov 23 2013
FORMULA
G.f.: 1/(1-23*x). - Philippe Deléham, Nov 23 2008
a(n)=23^n; a(n)=23*a(n-1) n>0 a(0)=1. - Vincenzo Librandi, Nov 21 2010
MATHEMATICA
23^Range[0, 20] (* Harvey P. Dale, Apr 04 2011 *)
PROG
(Sage) [lucas_number1(n, 23, 0) for n in range(1, 17)]# - Zerinvary Lajos, Apr 29 2009
(Magma)[23^n: n in [0..100]] // Vincenzo Librandi, Nov 21 2010
(Maxima) A009967(n):=23^n$
makelist(A009967(n), n, 0, 30); /* Martin Ettl, Nov 07 2012 */
(PARI) a(n)=23^n \\ Charles R Greathouse IV, Sep 24 2015
CROSSREFS
Sequence in context: A207223 A207010 A171297 * A147642 A057686 A042014
KEYWORD
nonn,easy
STATUS
approved