Number of descents beginning and ending with an odd number in all permutations of {1,2,...,n}.
A152885
Number of descents beginning and ending with an odd number in all permutations of {1,2,...,n}.
Terms
- a(0) =0a(1) =0a(2) =2a(3) =6a(4) =72a(5) =360a(6) =4320a(7) =30240a(8) =403200a(9) =3628800a(10) =54432000a(11) =598752000a(12) =10059033600a(13) =130767436800
External references
- oeis: A152885