a(n) = |Stirling1(n, floor(n/2))| * floor(n/2)!.

A344498

a(n) = |Stirling1(n, floor(n/2))| * floor(n/2)!.

Terms

    a(0) =1a(1) =0a(2) =1a(3) =2a(4) =22a(5) =100a(6) =1350a(7) =9744a(8) =162456a(9) =1614816a(10) =32319000a(11) =410031600a(12) =9604465200a(13) =148370508000

External references