Number of permutations of 1..n avoiding adjacent step pattern up, up, up, up.

A177523

Number of permutations of 1..n avoiding adjacent step pattern up, up, up, up.

Terms

    a(0) =1a(1) =1a(2) =2a(3) =6a(4) =24a(5) =119a(6) =709a(7) =4928a(8) =39144a(9) =349776a(10) =3472811a(11) =37928331a(12) =451891992a(13) =5832672456a(14) =81074690424

External references