a(n) is the permanent of the symmetric n X n matrix M_n where M_n(j,k) = n for j = k, M_n(j,n) = n-j, M_n(n,k) = n-k, M_n(j,k) = 0 otherwise.

A386974

a(n) is the permanent of the symmetric n X n matrix M_n where M_n(j,k) = n for j = k, M_n(j,n) = n-j, M_n(n,k) = n-k, M_n(j,k) = 0 otherwise.

Terms

    a(0) =1a(1) =1a(2) =5a(3) =42a(4) =480a(5) =6875a(6) =117936a(7) =2352980a(8) =53477376a(9) =1363146165a(10) =38500000000

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