E.g.f.: exp( Sum_{n>=1} x^(2*n) * Sum_{k=1..n} 1/k^2 ).

A235776

E.g.f.: exp( Sum_{n>=1} x^(2*n) * Sum_{k=1..n} 1/k^2 ).

Terms

    a(0) =1a(1) =2a(2) =42a(3) =2000a(4) =170660a(5) =22741992a(6) =4344779208

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