A178425 29 followed by the base-30 Fermat numbers.

29, 31, 901, 810001, 656100000001, 430467210000000000000001, 185302018885184100000000000000000000000000000001, 34336838202925124846578490892810000000000000000000000000000000000000000000000000000000000000001

Offset

0,1

Links

Table of n, a(n) for n=0..7.

Formula

a(n) = 30^(2^(n-1)) + 1, n > 0.

a(n) = 2 + Product_{i=0..n-1} a(i).

a(n) = 1 + (a(n-1)-1)^2, n > 1.

Product_{n>=0} (1 - 1/a(n)) = 14/15. - Amiram Eldar, Dec 01 2025

Mathematica

a[0] := 29;
a[n_] := a[n] = Product[a[i], {i, 0, n - 1}] + 2;
Table[a[n], {n, 0, 10}]

Crossrefs

Cf. A000215.

Sequence in context: A158342 A077286 A235364 * A344796 A294737 A261521

Adjacent sequences: A178422 A178423 A178424 * A178426 A178427 A178428

Keyword

nonn,easy

Author

Roger L. Bagula, May 27 2010

Extensions

Edited by the Assoc. Eds. of the OEIS, Jul 20 2010

Status

approved