Number of terms in a symmetrical determinant: a(n) = n*a(n-1) - (n-1)*(n-2)*a(n-3)/2.
A002135
Number of terms in a symmetrical determinant: a(n) = n*a(n-1) - (n-1)*(n-2)*a(n-3)/2.
Terms
- a(0) =1a(1) =1a(2) =2a(3) =5a(4) =17a(5) =73a(6) =388a(7) =2461a(8) =18155a(9) =152531a(10) =1436714a(11) =14986879a(12) =171453343a(13) =2134070335a(14) =28708008128a(15) =415017867707
External references
- oeis: A002135