A problem of configurations: a(0) = 1; for n>0, a(n) = (2n-1)!! - Sum_{k=1..n-1} (2k-1)!! a(n-k). Also the number of shellings of an n-cube, divided by 2^n n!.
A000698
A problem of configurations: a(0) = 1; for n>0, a(n) = (2n-1)!! - Sum_{k=1..n-1} (2k-1)!! a(n-k). Also the number of shellings of an n-cube, divided by 2^n n!.
Terms
- a(0) =1a(1) =1a(2) =2a(3) =10a(4) =74a(5) =706a(6) =8162a(7) =110410a(8) =1708394a(9) =29752066a(10) =576037442a(11) =12277827850a(12) =285764591114
External references
- oeis: A000698