1,2

The base block is not counted among the n and must be the only block in the bottom layer of the building.

Table of n, a(n) for n=1..8.

Cf. A112389, A123762 - A123827, A123829 - A123849.

Sequence in context: A019508 A166058 A305609 * A138842 A040462 A269310

Adjacent sequences: A123796 A123797 A123798 * A123800 A123801 A123802

nonn,more

Søren Eilers, Oct 29 2006

approved