Number of permutations of length n which avoid the patterns 1342, 2413, 3124 and 3142.

A295873

Number of permutations of length n which avoid the patterns 1342, 2413, 3124 and 3142.

Terms

    a(0) =1a(1) =1a(2) =2a(3) =6a(4) =20a(5) =68a(6) =231a(7) =781a(8) =2629a(9) =8821a(10) =29530a(11) =98706a(12) =329592a(13) =1099792a(14) =3668127a(15) =12230505a(16) =40771337a(17) =135895689a(18) =452914658a(19) =1509385902a(20) =5029980252a(21) =16761785436a(22) =55855539047a(23) =186125915029a(24) =620217261197

External references