a(n) = (1/4) * (number of n X n 0..11 matrices with MM' mod 12 = I).

A071310

a(n) = (1/4) * (number of n X n 0..11 matrices with MM' mod 12 = I).

Terms

    a(0) =1a(1) =32a(2) =4608a(3) =7077888a(4) =101921587200

External references