A052271 Number of n X n matrices over GF(4) under row and column permutations.

1, 4, 76, 8240, 7880456, 79846389608, 9178323524804624, 12508419942924578958856, 209493560585995285291677153144, 44407122853769773657258254744483639216, 122042291850117110186411151373496788803833567344, 4435666701292795500500326090033525002278314431436080593856

Offset

0,2

Links

Alois P. Heinz, Table of n, a(n) for n = 0..26

Index to number of inequivalent matrices modulo permutation of rows and columns

Formula

a(n) = sum_{1*s_1+2*s_2+...=n, 1*t_1+2*t_2+...=n} (fixA[s_1, s_2, ...;t_1, t_2,...]/(1^s_1*s_1!*2^s_2*s_2!*...*1^t_1*t_1!*2^t_2*t_2!*...)) where fixA[...] = 4^sum_{i, j>=1} (gcd(i,j)*s_i*t_j). - Christian G. Bower, Dec 18 2003

Crossrefs

Cf. A002724, A052269, A052272, A091061.

Column k=4 of A246106.

Sequence in context: A350489 A325214 A118193 * A184272 A080989 A006267

Adjacent sequences: A052268 A052269 A052270 * A052272 A052273 A052274

Keyword

nonn

Author

Vladeta Jovovic, Feb 05 2000

Extensions

More terms from Alois P. Heinz, Jul 31 2014

Status

approved