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: A194725 A218500 A293986 * A145509 A098782 A076758
Adjacent sequences: A123818 A123819 A123820 * A123822 A123823 A123824
Søren Eilers, Oct 29 2006