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A353945
Product_{n>=1} 1 / (1 - a(n)*x^n) = 1 + Sum_{n>=1} tau(n)*x^n, where tau = A000005.
3
1, 1, 0, 0, -1, 1, -1, 0, 1, -2, 0, 1, -1, -2, 2, 1, -2, -2, 2, 0, -4, 0, 3, -3, 3, -3, -2, -1, 1, 8, -15, 0, 17, -14, -1, -3, 9, -5, -18, 23, -10, -18, 24, -17, -17, 18, 27, -48, -37, 72, 45, -119, -11, 148, -98, -28, 65, -57, 24, -95, 213, -363, -173, 704, -435
OFFSET
1,10
FORMULA
Product_{n>=1} 1 / (1 - a(n)*x^n) = 1 + Sum_{n>=1} x^n / (1 - x^n).
MATHEMATICA
A[m_, n_] := A[m, n] = Which[m == 1, DivisorSigma[0, n], m > n >= 1, 0, True, A[m - 1, n] - A[m - 1, m - 1] A[m - 1, n - m + 1]]; a[n_] := A[n, n]; a /@ Range[1, 65]
KEYWORD
sign
AUTHOR
Ilya Gutkovskiy, May 12 2022
STATUS
approved