Number T(n,k) of permutations of [n] with exactly k (possibly overlapping) occurrences of the consecutive step pattern up, down, up, down; triangle T(n,k), n>=0, 0<=k<=max(0,floor((n-3)/2)), read by rows.
A230797
Number T(n,k) of permutations of [n] with exactly k (possibly overlapping) occurrences of the consecutive step pattern up, down, up, down; triangle T(n,k), n>=0, 0<=k<=max(0,floor((n-3)/2)), read by rows.
Terms
- a(0) =1a(1) =1a(2) =2a(3) =6a(4) =24a(5) =104a(6) =16a(7) =528a(8) =192a(9) =3296a(10) =1472a(11) =272a(12) =23168a(13) =12800a(14) =4352a(15) =179712a(16) =132352a(17) =42880a(18) =7936a(19) =1573632a(20) =1366016a(21) =530432a(22) =158720a(23) =15207424a(24) =14781952a(25) =7662336a(26) =1911296a(27) =353792a(28) =158880768a(29) =178102272
External references
- oeis: A230797