A001585 - OEIS

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A001585

a(n) = 3^n + n^3.

1, 4, 17, 54, 145, 368, 945, 2530, 7073, 20412, 60049, 178478, 533169, 1596520, 4785713, 14352282, 43050817, 129145076, 387426321, 1162268326, 3486792401, 10460362464, 31381070257, 94143190994, 282429550305, 847288625068

(list; graph; refs; listen; history; text; internal format)

OFFSET

0,2

COMMENTS

In this sequence if we do a forward difference, then the 4th forward difference when considered as a sequence will be a geometric progression with common ratio 3. - Gopalakrishnan (gopala498(AT)yahoo.co.in), May 26 2010

LINKS

Vincenzo Librandi, Table of n, a(n) for n = 0..1000

R. K. Hoeflin, Titan Test

Index entries for linear recurrences with constant coefficients, signature (7, -18, 22, -13, 3).

FORMULA

G.f.: (-1+2*x^4+15*x^3-7*x^2+3*x)/((3*x-1)*(x-1)^4). - Maksym Voznyy (voznyy(AT)mail.ru), Jul 27 2009

MAPLE

seq(seq(k^n+n^k, k=3..3), n=0..23); # Zerinvary Lajos, Jun 29 2007

MATHEMATICA

Table[3^n+n^3, {n, 0, 3*4!}] (* Vladimir Joseph Stephan Orlovsky, May 07 2010 *)

PROG

(Magma) [3^n+n^3: n in [0..30]]; // Vincenzo Librandi, Oct 27 2011