a(n) = 2^n * Product_{k=1..n} (4*k*(4*k+2))^(n-k).

A168442

a(n) = 2^n * Product_{k=1..n} (4*k*(4*k+2))^(n-k).

Terms

    a(0) =1a(1) =2a(2) =96a(3) =368640a(4) =237817036800

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