Number of ascent sequences of length n with exactly one flat step.

A242154

Number of ascent sequences of length n with exactly one flat step.

Terms

    a(0) =1a(1) =2a(2) =6a(3) =20a(4) =80a(5) =366a(6) =1897a(7) =10976a(8) =70155a(9) =490930a(10) =3733246a(11) =30655152a(12) =270334766a(13) =2548153230a(14) =25566585450a(15) =272052199520

External references