Subtract compositions (A011782) from Catalan numbers (A000108).

Terms

a(0) =0a(1) =0a(2) =0a(3) =1a(4) =6a(5) =26a(6) =100a(7) =365a(8) =1302a(9) =4606a(10) =16284a(11) =57762a(12) =205964a(13) =738804a(14) =2666248a(15) =9678461a(16) =35324902a(17) =129579254a(18) =477507628a(19) =1767001046a(20) =6563596132a(21) =24465218444a(22) =91480466488a(23) =343055419346