Let t = coefficient of x^(2n+1) in expansion of sin(x)/(1-x^2); a(n)=denominator(t)-numerator(t).

A067621

Let t = coefficient of x^(2n+1) in expansion of sin(x)/(1-x^2); a(n)=denominator(t)-numerator(t).

Terms

    a(0) =0a(1) =1a(2) =19a(3) =799a(4) =57527a(5) =6327971a(6) =39486539a(7) =207304329751

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