Number of length-n permutations avoiding descent patterns aba and bab.

A295974

Number of length-n permutations avoiding descent patterns aba and bab.

Terms

    a(0) =1a(1) =1a(2) =2a(3) =6a(4) =14a(5) =52a(6) =204a(7) =1010a(8) =5466a(9) =34090a(10) =233026a(11) =1765836a(12) =14534404a(13) =129916550a(14) =1248875862a(15) =12872804422a(16) =141470905326

External references