a(n) = (C(2p,p)-2) / p^3, where p = prime(n).

A087754

a(n) = (C(2p,p)-2) / p^3, where p = prime(n).

Terms

    a(0) =2a(1) =10a(2) =530a(3) =4734a(4) =474986a(5) =5153122a(6) =676701794

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