Number T(n,k) of involutions of [n] having exactly k peaks; triangle T(n,k), n>=0, 0<=k<=max(0,floor((n-1)/2)), read by rows.

A303648

Number T(n,k) of involutions of [n] having exactly k peaks; triangle T(n,k), n>=0, 0<=k<=max(0,floor((n-1)/2)), read by rows.

Terms

    a(0) =1a(1) =1a(2) =2a(3) =3a(4) =1a(5) =4a(6) =6a(7) =5a(8) =18a(9) =3a(10) =6a(11) =44a(12) =26a(13) =7a(14) =91a(15) =123a(16) =11a(17) =8a(18) =172a(19) =448a(20) =136a(21) =9a(22) =300a(23) =1348a(24) =912a(25) =51a(26) =10a(27) =496a(28) =3600a(29) =4552

External references