One half of the number of permutations of [n] such that the differences have 4 runs with the same signs.

A000486

One half of the number of permutations of [n] such that the differences have 4 runs with the same signs.

Terms

    a(0) =16a(1) =150a(2) =926a(3) =4788a(4) =22548a(5) =100530a(6) =433162a(7) =1825296a(8) =7577120a(9) =31130190a(10) =126969558a(11) =515183724a(12) =2082553132a(13) =8395437930a(14) =33776903714a(15) =135691891272a(16) =544517772984

External references