%I A091061
%S A091061 1,1,9,408,332034,3327329224,382430372929443,521184164586987473279,
%T A091061 8728898357751671813141271503,1850296785573740600565249566845514268,
%U A091061 5085095493754879591102840109774321148107411672
%N A091061 Number of n X n matrices over symbol set {1,2,3,4} equivalent under any
permutation of row, columns or the symbol set.
%H A091061 C. G. Bower, <a href="a091057.html">Explanation of A091057-A091062</a>
%F A091061 a(n) = sum {1*s_1+2*s_2+...=n, 1*t_1+2*t_2+...=n, 1*u_1+2*u_2+...=4}
(fix A[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 fix A[...] = prod {i, j>=1} ( (sum
{d|lcm(i, j)} (d*u_d))^(gcd(i, j)*s_i*t_j))
%Y A091061 Cf. A091057-A091062.
%Y A091061 Sequence in context: A058850 A151632 A035024 this_sequence A024123 A081481
A160376
%Y A091061 Adjacent sequences: A091058 A091059 A091060 this_sequence A091062 A091063
A091064
%K A091061 nonn
%O A091061 0,3
%A A091061 Christian G. Bower (bowerc(AT)usa.net), Dec 17 2003
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