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A091062
Number of n X n matrices over symbol set {1,2,3,4,5} equivalent under any permutation of row, columns or the symbol set.
9
1, 1, 9, 649, 2283123, 173636442196, 234378355489344704, 5830719097591168695360621, 2779203181367458204944451774688032, 26174539685600184383643311230836752183522328, 4992259182572292655057303928366260085844535079288641049
OFFSET
0,3
FORMULA
a(n) = sum_{1*s_1+2*s_2+...=n, 1*t_1+2*t_2+...=n, 1*u_1+2*u_2+...=5} (fixA[s_1, s_2, ...;t_1, t_2, ...;u_1, u_2, ...]/(1^s_1*s_1!*2^s_2*s_2!* ... *1^t_1*t_1!*2^t_2*t_2!* ... *1^u_1*u_1!*2^u_2*u_2!*...)) where fixA[...] = prod_{i, j>=1} ( (sum_{d|lcm(i, j)} (d*u_d))^(gcd(i, j)*s_i*t_j)).
CROSSREFS
Column k=5 of A242095.
Sequence in context: A191510 A081232 A020548 * A221133 A015007 A054327
KEYWORD
nonn
AUTHOR
Christian G. Bower, Dec 17 2003
EXTENSIONS
a(10) from Alois P. Heinz, Aug 14 2014
STATUS
approved