a(n) = n! * Sum_{k=0..floor(n/2)} (-k/2)^k / (k! * (n-2*k)!).

A362340

a(n) = n! * Sum_{k=0..floor(n/2)} (-k/2)^k / (k! * (n-2*k)!).

Terms

    a(0) =1a(1) =1a(2) =0a(3) =-2a(4) =7a(5) =51a(6) =-239a(7) =-2435a(8) =16353a(9) =209377a(10) =-1826099a(11) =-28232379a(12) =303020125a(13) =5494172893a(14) =-70032035163

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