Number of permutations of length n which avoid the patterns 2143, 2341, 4312; or avoid the patterns 1234, 1432, 3412.

A116774

Number of permutations of length n which avoid the patterns 2143, 2341, 4312; or avoid the patterns 1234, 1432, 3412.

Terms

    a(0) =1a(1) =2a(2) =6a(3) =21a(4) =69a(5) =198a(6) =498a(7) =1121a(8) =2305a(9) =4402a(10) =7910a(11) =13509a(12) =22101a(13) =34854a(14) =53250a(15) =79137a(16) =114785a(17) =162946a(18) =226918a(19) =310613a(20) =418629a(21) =556326a(22) =729906a(23) =946497a(24) =1214241a(25) =1542386a(26) =1941382a(27) =2422981a(28) =3000341a(29) =3688134

External references