Number of valid hook configurations of 132-avoiding permutations of [n].

Terms

a(0) =1a(1) =1a(2) =1a(3) =2a(4) =5a(5) =14a(6) =43a(7) =140a(8) =477a(9) =1683a(10) =6106a(11) =22664a(12) =85735a(13) =329572a(14) =1284440a(15) =5065828a(16) =20188877a(17) =81201801a(18) =329281059a(19) =1345059602a(20) =5530600618a(21) =22876354484a(22) =95137126194a(23) =397610249052