a(n + 4) = (n + 2)*(a(n + 3) - a(n) + 1) for n > 3, a(0) = a(1) = a(2) = a(3) = 1.
A121987
a(n + 4) = (n + 2)*(a(n + 3) - a(n) + 1) for n > 3, a(0) = a(1) = a(2) = a(3) = 1.
Terms
- a(0) =1a(1) =1a(2) =1a(3) =1a(4) =2a(5) =6a(6) =24a(7) =120a(8) =714a(9) =4963a(10) =39520a(11) =354609a(12) =3538960a(13) =38873978a(14) =466013508a(15) =6053565700a(16) =84700374374
External references
- oeis: A121987