a(1)=a(2)=1; a(n) = a(n-1)*a(n-2) + a(n-3) + a(n-4) + ... + a(1) for n>2.

A117157

a(1)=a(2)=1; a(n) = a(n-1)*a(n-2) + a(n-3) + a(n-4) + ... + a(1) for n>2.

Terms

    a(0) =1a(1) =1a(2) =1a(3) =2a(4) =4a(5) =11a(6) =49a(7) =548a(8) =26872a(9) =14725925a(10) =395715057217

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