Irregular triangle: T(n,k) is the number of permutations in S_n that have exactly k occurrences of the pattern 4213. 0 <= k <= A342646(n).
A342840
Irregular triangle: T(n,k) is the number of permutations in S_n that have exactly k occurrences of the pattern 4213. 0 <= k <= A342646(n).
Terms
- a(0) =1a(1) =1a(2) =2a(3) =6a(4) =23a(5) =1a(6) =103a(7) =10a(8) =6a(9) =1a(10) =512a(11) =77a(12) =69a(13) =30a(14) =21a(15) =5a(16) =6a(17) =2740a(18) =548a(19) =598a(20) =330a(21) =335a(22) =123a(23) =174a(24) =58a(25) =58a(26) =37a(27) =26a(28) =3a(29) =9
External references
- oeis: A342840