Number of permutations of length n which avoid the patterns 321, 2143, 3124; or avoid the patterns 132, 2314, 4312, etc.

A116731

Number of permutations of length n which avoid the patterns 321, 2143, 3124; or avoid the patterns 132, 2314, 4312, etc.

Terms

    a(0) =1a(1) =2a(2) =5a(3) =12a(4) =25a(5) =46a(6) =77a(7) =120a(8) =177a(9) =250a(10) =341a(11) =452a(12) =585a(13) =742a(14) =925a(15) =1136a(16) =1377a(17) =1650a(18) =1957a(19) =2300a(20) =2681a(21) =3102a(22) =3565a(23) =4072a(24) =4625a(25) =5226a(26) =5877a(27) =6580a(28) =7337a(29) =8150

External references