a(n) = Product_{k=0..n} (2^k + 2^(n-k)).

A369673

a(n) = Product_{k=0..n} (2^k + 2^(n-k)).

Terms

    a(0) =2a(1) =9a(2) =100a(3) =2916a(4) =231200a(5) =50808384a(6) =31258240000

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