Write x*cot(x) = Product_{n>=1} (1 + g_n*x^(2*n)); a(n) = denominator(g_n).

A170921

Write x*cot(x) = Product_{n>=1} (1 + g_n*x^(2*n)); a(n) = denominator(g_n).

Terms

    a(0) =3a(1) =45a(2) =105a(3) =4725a(4) =66825a(5) =127702575a(6) =383107725a(7) =18091198125

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