A122250 Partial sums of A004128.

0, 1, 3, 7, 12, 18, 26, 35, 45, 58, 72, 87, 104, 122, 141, 162, 184, 207, 233, 260, 288, 318, 349, 381, 415, 450, 486, 526, 567, 609, 653, 698, 744, 792, 841, 891, 944, 998, 1053, 1110, 1168

Offset

0,3

Links

G. C. Greubel, Table of n, a(n) for n = 0..1000

Formula

G.f.: (1/(1-x))*Sum{k=0..infinity} ( x^(3^k)/((1-x)*(1-x^(3^k))) ).

a(n) = Sum_{j=0..n} ( Sum_{k=0..j} floor(j/3^k) ).

Mathematica

Table[Sum[Sum[Floor[3*j/3^k], {k, 1, j}], {j, 0, n}], {n, 0, 50}] (* G. C. Greubel, May 14 2017 *)

Prog

(PARI) for(n=0, 50, print1(sum(j=0, n, sum(k=0, j, floor(j/3^k))), ", ")) \\ G. C. Greubel, May 14 2017

Crossrefs

Sequence in context: A005228 A000969 A194117 * A169679 A024388 A184534

Adjacent sequences: A122247 A122248 A122249 * A122251 A122252 A122253

Keyword

easy,nonn

Author

Paul Barry, Aug 27 2006

Status

approved