a(n) = (1/2) * (number of n X n 0..2 matrices M with MM' mod 3 = I, where M' is the transpose of M and I is the n X n identity matrix).

A071302

a(n) = (1/2) * (number of n X n 0..2 matrices M with MM' mod 3 = I, where M' is the transpose of M and I is the n X n identity matrix).

Terms

    a(0) =1a(1) =4a(2) =24a(3) =576a(4) =51840a(5) =13063680a(6) =9170703360

External references