A225585 Floor((3^n-1)/n).

2, 4, 8, 20, 48, 121, 312, 820, 2186, 5904, 16104, 44286, 122640, 341640, 956593, 2690420, 7596480, 21523360, 61171656, 174339220, 498112057, 1426411800, 4093181688, 11767897353, 33891544377, 97764070320, 282429536480, 817028301962, 2366564736720

Offset

1,1

Links

Vincenzo Librandi, Table of n, a(n) for n = 1..300

Mathematica

Table[Floor[(3^n - 1) / n], {n, 30}] (* or *) Table[Quotient[3^n - 1, n], {n, 30}]

Prog

(Magma) [Floor((3^n-1)/n): n in [1..30]];

Crossrefs

Cf. A003462, A007051, A024023, A034472, A082482, A092763.

Sequence in context: A338197 A056952 A369496 * A121703 A301467 A358056

Adjacent sequences: A225582 A225583 A225584 * A225586 A225587 A225588

Keyword

nonn,easy

Author

Vincenzo Librandi, May 30 2013

Status

approved