Number of permutations of length n which avoid the patterns 4312 and 3142.

A165538

Number of permutations of length n which avoid the patterns 4312 and 3142.

Terms

    a(0) =1a(1) =1a(2) =2a(3) =6a(4) =22a(5) =88a(6) =367a(7) =1568a(8) =6810a(9) =29943a(10) =132958a(11) =595227a(12) =2683373a(13) =12170778a(14) =55499358a(15) =254297805a(16) =1170248190a(17) =5406570910a(18) =25068420955a(19) =116617923611a(20) =544157590706

External references