Number T(n,k) of permutations of [n] with exactly k (possibly overlapping) occurrences of the consecutive step pattern up, down, up; triangle T(n,k), n>=0, 0<=k<=max(0,floor(n/2)-1), read by rows.
A227884
Number T(n,k) of permutations of [n] with exactly k (possibly overlapping) occurrences of the consecutive step pattern up, down, up; triangle T(n,k), n>=0, 0<=k<=max(0,floor(n/2)-1), read by rows.
Terms
- a(0) =1a(1) =1a(2) =2a(3) =6a(4) =19a(5) =5a(6) =70a(7) =50a(8) =331a(9) =328a(10) =61a(11) =1863a(12) =2154a(13) =1023a(14) =11637a(15) =16751a(16) =10547a(17) =1385a(18) =81110a(19) =144840a(20) =102030a(21) =34900a(22) =635550a(23) =1314149a(24) =1109973a(25) =518607a(26) =50521a(27) =5495339a(28) =12735722a(29) =13046040
External references
- oeis: A227884