G.f.: Sum_{n>=0} Product_{k=0..n-1} ( (1+x)^(n+k) - 1 ).

A338176

G.f.: Sum_{n>=0} Product_{k=0..n-1} ( (1+x)^(n+k) - 1 ).

Terms

    a(0) =1a(1) =1a(2) =6a(3) =69a(4) =1115a(5) =23271a(6) =594755a(7) =17983607a(8) =627836008a(9) =24851815494

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