Irregular triangle read by rows: T(n,k) is the number of n-permutations whose second-longest cycle has length exactly k; n>=0, 0<=k<=floor(n/2).

A349979

Irregular triangle read by rows: T(n,k) is the number of n-permutations whose second-longest cycle has length exactly k; n>=0, 0<=k<=floor(n/2).

Terms

    a(0) =1a(1) =1a(2) =1a(3) =1a(4) =2a(5) =4a(6) =6a(7) =15a(8) =3a(9) =24a(10) =61a(11) =35a(12) =120a(13) =290a(14) =270a(15) =40a(16) =720a(17) =1646a(18) =1974a(19) =700a(20) =5040a(21) =11025a(22) =14707a(23) =8288a(24) =1260a(25) =40320a(26) =85345a(27) =117459a(28) =90272a(29) =29484

External references