A146196 Number of n X n arrays of squares of integers with every (n-3)X(n-3) subblock summing to 5 and every element equal to at least one neighbor.

0, 540, 24646, 108226, 315281, 734060, 1477489, 2682776, 4511681, 7150588, 10810505, 15727064, 22160521, 30395756, 40742273, 53534200, 69130289, 87913916, 110293081

Offset: 5

Author

R. H. Hardin Apr 14 2009

Keywords

• nonn

Formula

Empirical (for n>=10): a(n) = 1026*n^4 - 20236*n^3 + 152815*n^2 - 529236*n + 720920. - Vaclav Kotesovec, Nov 30 2012