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A009975
Powers of 31: a(n) = 31^n.
45
1, 31, 961, 29791, 923521, 28629151, 887503681, 27512614111, 852891037441, 26439622160671, 819628286980801, 25408476896404831, 787662783788549761, 24417546297445042591, 756943935220796320321, 23465261991844685929951, 727423121747185263828481
OFFSET
0,2
COMMENTS
Same as Pisot sequences E(1, 31), L(1, 31), P(1, 31), T(1, 31). Essentially same as Pisot sequences E(31, 961), L(31, 961), P(31, 961), T(31, 961). 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 31-colored compositions of n such that no adjacent parts have the same color. - Milan Janjic, Nov 17 2011
FORMULA
G.f.: 1/(1-31*x). - Philippe Deléham, Nov 24 2008
E.g.f.: exp(31x). - Geoffrey Critzer, Feb 28 2009
a(n) = 31*a(n-1). - Zerinvary Lajos, Apr 29 2009
MATHEMATICA
Table[31^n, {n, 0, 15}] (* Robert P. P. McKone, Jan 04 2022 *)
PROG
(PARI) a(n)=31^n \\ Charles R Greathouse IV, Sep 24 2015
CROSSREFS
Sequence in context: A207431 A208373 A171305 * A042862 A159674 A138958
KEYWORD
nonn,easy
STATUS
approved

  NODES
orte 1
see 2
Story 1