Triangle read by rows related to enumeration of permutations avoiding certain patterns.

Terms

a(0) =1a(1) =1a(2) =1a(3) =1a(4) =4a(5) =1a(6) =1a(7) =10a(8) =9a(9) =1a(10) =20a(11) =41a(12) =6a(13) =1a(14) =35a(15) =133a(16) =61a(17) =2a(18) =1a(19) =56a(20) =350a(21) =336a(22) =49a(23) =1a(24) =84a(25) =798a(26) =1336a(27) =465a(28) =20a(29) =1