a(n) = ( Product {k = 1..n} 3*k - 2 ) * ( Sum {k = 1..n} (-1)^(k+1)/(3*k - 2) ).

A024217

a(n) = ( Product {k = 1..n} 3*k - 2 ) * ( Sum {k = 1..n} (-1)^(k+1)/(3*k - 2) ).

Terms

    a(0) =1a(1) =3a(2) =25a(3) =222a(4) =3166a(5) =47016a(6) =951544a(7) =19827408a(8) =520029520a(9) =13952218560a(10) =449559799360

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