Number of permutations of 3 copies of 1..n introduced in order 1..n with no element equal to another within a distance of 4.

A190829

Number of permutations of 3 copies of 1..n introduced in order 1..n with no element equal to another within a distance of 4.

Terms

    a(0) =0a(1) =0a(2) =0a(3) =0a(4) =1a(5) =1744a(6) =930776a(7) =403365340a(8) =183903095593

External references