1,8

Table of n, a(n) for n=1..20.

Three collinear points in an n X n grid A000938 ; n X n X n grid A157882

Sequence in context: A135409 A203349 A262092 * A081864 A002594 A194134

Adjacent sequences: A178263 A178264 A178265 * A178267 A178268 A178269

nonn

R. H. Hardin, suggested by R. J. Mathar in the Sequence Fans Mailing List, May 24 2010

approved