a(n) = n! * Sum_{k=0..floor(n/5)} n^k / (k! * (n-5*k)!).

A362323

a(n) = n! * Sum_{k=0..floor(n/5)} n^k / (k! * (n-5*k)!).

Terms

    a(0) =1a(1) =1a(2) =1a(3) =1a(4) =1a(5) =601a(6) =4321a(7) =17641a(8) =53761a(9) =136081a(10) =181742401a(11) =2415576241a(12) =17245198081a(13) =87699217321a(14) =355981385761

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