160129domain: NAppears in sequencesa(n) = (n^4 - n^3 + 4*n^2 + 2)/2.at n=24A239592Number of vertices formed by drawing the lines connecting any two of the 2*(n+2) perimeter points of a 3 X (n+1) rectangular grid of points (or equally, a 2 X n grid of squares).at n=30A331763