Irregular triangle read by rows: T(n,k) is the number of permutations of {1,2,...,n} having k white corners.
A140711
Irregular triangle read by rows: T(n,k) is the number of permutations of {1,2,...,n} having k white corners.
Terms
- a(0) =1a(1) =1a(2) =1a(3) =1a(4) =4a(5) =1a(6) =1a(7) =10a(8) =12a(9) =1a(10) =1a(11) =20a(12) =62a(13) =36a(14) =1a(15) =1a(16) =35a(17) =217a(18) =339a(19) =126a(20) =2a(21) =1a(22) =56a(23) =602a(24) =1880a(25) =1907a(26) =572a(27) =22a(28) =1a(29) =84
External references
- oeis: A140711