Number of permutations of length n which avoid the patterns 2314, 4213, 4312.

Terms

a(0) =1a(1) =2a(2) =6a(3) =21a(4) =75a(5) =262a(6) =891a(7) =2964a(8) =9700a(9) =31374a(10) =100639a(11) =320949a(12) =1019396a(13) =3228687a(14) =10206180a(15) =32219494a(16) =101619194a(17) =320303001a(18) =1009163739a(19) =3178610330a(20) =10009874543a(21) =31518335944a(22) =99233864812a(23) =312414443206a(24) =983524845979