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A052271 Number of n X n matrices over GF(4) under row and column permutations. 8
1, 4, 76, 8240, 7880456, 79846389608, 9178323524804624, 12508419942924578958856, 209493560585995285291677153144, 44407122853769773657258254744483639216 (list; graph; refs; listen; history; internal format)
OFFSET

0,2

FORMULA

a(n) = sum {1*s_1+2*s_2+...=n, 1*t_1+2*t_2+...=n} (fix A[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 fix A[...] = 4^sum {i, j>=1} (gcd(i, j)*s_i*t_j) - Christian G. Bower (bowerc(AT)usa.net), Dec 18 2003

CROSSREFS

Cf. A002724, A052269, A052272, A091061.

Sequence in context: A012010 A012155 A118193 * A184272 A080989 A006267

Adjacent sequences:  A052268 A052269 A052270 * A052272 A052273 A052274

KEYWORD

nonn

AUTHOR

Vladeta Jovovic (vladeta(AT)eunet.rs), Feb 05 2000

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Last modified February 15 15:20 EST 2012. Contains 205823 sequences.