0,3

C. G. Bower, Explanation of A091057-A091062

a(n) = sum {1*s_1+2*s_2+...=n, 1*t_1+2*t_2+...=n, 1*u_1+2*u_2+...=n} (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))

Cf. A091058-A091062.

Sequence in context: A145183 A124417 A159356 this_sequence A137065 A015025 A027878

Adjacent sequences: A091054 A091055 A091056 this_sequence A091058 A091059 A091060

nonn,more

Christian G. Bower (bowerc(AT)usa.net), Dec 17 2003