The number of sum decomposable permutations which avoid the patterns 3124 and 4312.

A226434

The number of sum decomposable permutations which avoid the patterns 3124 and 4312.

Terms

    a(0) =0a(1) =1a(2) =3a(3) =10a(4) =37a(5) =146a(6) =595a(7) =2456a(8) =10167a(9) =42027a(10) =173201a(11) =711397a(12) =2912633a(13) =11891030a(14) =48425597a(15) =196790382a(16) =798251109a(17) =3232928429a(18) =13075849791a(19) =52825304031a(20) =213196622183a(21) =859690304703

External references