Triangle read by rows: T(n,k) is the number of permutations of [1..n] with k modular progressions of rise 2, distance 1 and length 3 (n >= 0, k >= 0).
A216724
Triangle read by rows: T(n,k) is the number of permutations of [1..n] with k modular progressions of rise 2, distance 1 and length 3 (n >= 0, k >= 0).
Terms
- a(0) =1a(1) =1a(2) =2a(3) =3a(4) =3a(5) =24a(6) =0a(7) =100a(8) =15a(9) =0a(10) =5a(11) =594a(12) =108a(13) =18a(14) =0a(15) =4389a(16) =504a(17) =119a(18) =21a(19) =0a(20) =7a(21) =35744a(22) =3520a(23) =960a(24) =64a(25) =32a(26) =0a(27) =325395a(28) =31077a(29) =5238
External references
- oeis: A216724