Triangular array read by rows. T(n,k) is the number of functions f:{1,2,...,n}->{1,2,...,n} that have exactly k 3-cycles. n>=0, 0<=k<=floor(n/3).
A185070
Triangular array read by rows. T(n,k) is the number of functions f:{1,2,...,n}->{1,2,...,n} that have exactly k 3-cycles. n>=0, 0<=k<=floor(n/3).
Terms
- a(0) =1a(1) =1a(2) =4a(3) =25a(4) =2a(5) =224a(6) =32a(7) =2625a(8) =500a(9) =38056a(10) =8560a(11) =40a(12) =657433a(13) =164150a(14) =1960a(15) =13178880a(16) =3526656a(17) =71680a(18) =300585601a(19) =84389928a(20) =2442720a(21) =2240a(22) =7683776000a(23) =2232672000a(24) =83328000a(25) =224000a(26) =217534555161a(27) =64830707370a(28) =2931500880a(29) =14907200
External references
- oeis: A185070