A277357 a(1) = 1; for n > 1, a(n) = (2^n-1)*a(n-1) + 1.

1, 4, 29, 436, 13517, 851572, 108149645, 27578159476, 14092439492237, 14416565600558452, 29510709784343151245, 120846356566885204348276, 989852506639356708816728717, 16216753616272580960544466570612, 531374365744403660334160536119243405

Offset

1,2

Links

Table of n, a(n) for n=1..15.

Formula

a(n) ~ c * 2^(n*(n+1)/2), where c = 0.3997494420337372941776146353642774...

Mathematica

RecurrenceTable[{a[n]==(2^n-1)*a[n-1]+1, a[1]==1}, a, {n, 1, 15}]

Prog

(PARI) a(n) = if (n==1, 1, (2^n-1)*a(n-1) + 1); \\ Michel Marcus, Sep 30 2017

Crossrefs

Cf. A123672.

Sequence in context: A370165 A162287 A324227 * A173715 A230326 A272869

Adjacent sequences: A277354 A277355 A277356 * A277358 A277359 A277360

Keyword

nonn

Author

Vaclav Kotesovec, Oct 10 2016

Status

approved