Triangle read by rows: number of (1-2-3)-avoiding permutations on n letters with k peaks.

Terms

a(0) =1a(1) =1a(2) =2a(3) =3a(4) =2a(5) =4a(6) =10a(7) =5a(8) =32a(9) =5a(10) =6a(11) =84a(12) =42a(13) =7a(14) =198a(15) =210a(16) =14a(17) =8a(18) =438a(19) =816a(20) =168a(21) =9a(22) =932a(23) =2727a(24) =1152a(25) =42a(26) =10a(27) =1936a(28) =8250a(29) =5940