A081414 Largest prime divisor of prime(2^n+1) - prime(2^n).

1, 2, 2, 2, 3, 3, 2, 2, 2, 2, 3, 3, 3, 5, 2, 3, 3, 2, 3, 2, 13, 5, 17, 2, 5, 5, 5, 2, 5, 3, 7, 2, 3, 11, 3, 3, 13, 5, 11, 2, 5, 3, 3, 5, 7, 2, 3, 3, 2, 7, 2, 5, 7, 3, 7, 37, 7, 5, 17, 7, 11, 11, 13, 3, 3, 3, 43, 43, 3, 3, 7, 3, 5, 3, 5, 11, 3, 5, 3

Offset

0,2

Links

Table of n, a(n) for n=0..78.

Formula

a(n) = A006530(A001223(A000079(n))) = A081412(2^n) = A006530(A074325(n)).

Crossrefs

Cf. A006530, A001223, A000079, A081412, A081413, A074325.

Sequence in context: A354226 A341421 A308890 * A328577 A094321 A107789

Adjacent sequences: A081411 A081412 A081413 * A081415 A081416 A081417

Keyword

nonn

Author

Labos Elemer, Apr 02 2003

Extensions

Three more terms from Max Alekseyev, May 15 2009

Offset changed to 0, a(0) prepended and more terms added by Amiram Eldar, Jun 04 2024

Status

approved