Triangle read by rows: T(n,k) is the number of permutations of {1,2,...,n} having k nonincreasing cycles (0<=k<=floor(n/3)). A cycle (b(1), b(2), ...) is said to be increasing if, when written with its smallest element in the first position, it satisfies b(1) < b(2) < b(3) < ... .

A186756

Triangle read by rows: T(n,k) is the number of permutations of {1,2,...,n} having k nonincreasing cycles (0<=k<=floor(n/3)). A cycle (b(1), b(2), ...) is said to be increasing if, when written with its smallest element in the first position, it satisfies b(1) < b(2) < b(3) < ... .

Terms

    a(0) =1a(1) =1a(2) =2a(3) =5a(4) =1a(5) =15a(6) =9a(7) =52a(8) =68a(9) =203a(10) =507a(11) =10a(12) =877a(13) =3918a(14) =245a(15) =4140a(16) =32057a(17) =4123a(18) =21147a(19) =280700a(20) =60753a(21) =280a(22) =115975a(23) =2645611a(24) =853914a(25) =13300a(26) =678570a(27) =26917867a(28) =11923428a(29) =396935

External references