1,4

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..10.

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

Sequence in context: A143454 A318774 A065810 * A125620 A310687 A310688

Adjacent sequences: A123834 A123835 A123836 * A123838 A123839 A123840

nonn

Søren Eilers, Oct 29 2006

approved