Number of alternating 4-signed permutations.

A006873

Number of alternating 4-signed permutations.

Terms

    a(0) =1a(1) =1a(2) =7a(3) =47a(4) =497a(5) =6241a(6) =95767a(7) =1704527a(8) =34741217a(9) =796079041a(10) =20273087527a(11) =567864586607

External references