1,1

From a puzzle proposed by Marc LeBrun.

Table of n, a(n) for n=1..51.

Sequence in context: A288610 A062607 A018768 * A004235 A004236 A153049

Adjacent sequences: A045967 A045968 A045969 * A045971 A045972 A045973

easy,nonn

N. J. A. Sloane

More terms from David W. Wilson

approved