131720

Appears in sequences

• Number of 2 X 2 regular integer matrices with elements from {0,...,n} up to row and column permutation.at n=26A064363
• a(n) is the number of rotation-reflection inequivalent solutions to the all-ones lights out problem on an n X n square.at n=29A075463
• a(n) is the number of rotation-reflection inequivalent solutions to the all-ones lights out problem on an n X n square.at n=31A075463