2,2

I. Jensen, Table of n, a(n) for n = 2..43 (from link below)

I. Jensen, More terms

Cf. A056625.

Sequence in context: A015575 A152109 A124152 this_sequence A152263 A142986 A123511

Adjacent sequences: A056628 A056629 A056630 this_sequence A056632 A056633 A056634

nonn

N. J. A. Sloane (njas(AT)research.att.com), Aug 30 2000