Let u(1)=0, u(2)=1, u(k)=u(k-1)+u(k-2)/(k-2); then a(n)=n!*u(n).

A086325

Let u(1)=0, u(2)=1, u(k)=u(k-1)+u(k-2)/(k-2); then a(n)=n!*u(n).

Terms

    a(0) =0a(1) =2a(2) =6a(3) =36a(4) =220a(5) =1590a(6) =12978a(7) =118664a(8) =1201464a(9) =13349610a(10) =161530270a(11) =2114578092a(12) =29780308116a(13) =448995414686

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