A002901 n^3 - floor( n/3 ).

0, 1, 8, 26, 63, 124, 214, 341, 510, 726, 997, 1328, 1724, 2193, 2740, 3370, 4091, 4908, 5826, 6853, 7994, 9254, 10641, 12160, 13816, 15617, 17568, 19674, 21943, 24380, 26990, 29781, 32758, 35926, 39293

Offset

0,3

Links

Table of n, a(n) for n=0..34.

Index entries for linear recurrences with constant coefficients, signature (3,-3,2,-3,3,-1).

Formula

G.f. x*(1+5*x+5*x^2+7*x^3) / ( (1+x+x^2)*(x-1)^4 ). - R. J. Mathar, Mar 08 2013

a(n) = A000578(n)- A002264(n). - Michel Marcus, Jun 19 2013

Mathematica

Table[n^3-Floor[n/3], {n, 0, 40}] (* or *) LinearRecurrence[{3, -3, 2, -3, 3, -1}, {0, 1, 8, 26, 63, 124}, 40] (* Harvey P. Dale, Apr 23 2020 *)

Prog

(PARI) a(n) = n^3 - floor( n/3 ) \\ Michel Marcus, Jun 19 2013

Crossrefs

Sequence in context: A250352 A213039 A211640 * A350163 A213769 A301647

Adjacent sequences: A002898 A002899 A002900 * A002902 A002903 A002904

Keyword

nonn,easy

Author

ochavez(AT)spin.com.mx (Oscar Chavez)

Status

approved