I would very much like to find a formula for this - N. J. A. Sloane.
Table of n, a(n) for n=0..9.
Sequence in context: A007808 A104989 A119906 * A274379 A192209 A154677
Adjacent sequences: A059723 A059724 A059725 * A059727 A059728 A059729
N. J. A. Sloane, Feb 09 2001