a(0) = 1 and a(n) = Sum_{k = 0..2*n} n/(n + 2*k)*binomial(n + 2*k,k) for n >= 1.

A352275

a(0) = 1 and a(n) = Sum_{k = 0..2*n} n/(n + 2*k)*binomial(n + 2*k,k) for n >= 1.

Terms

    a(0) =1a(1) =4a(2) =64a(3) =1429a(4) =35072a(5) =898129a(6) =23571781a(7) =628750217a(8) =16965558016a(9) =461752375705

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