Number of reversible strings with n beads using exactly five different colors.

A056312

Number of reversible strings with n beads using exactly five different colors.

Terms

    a(0) =0a(1) =0a(2) =0a(3) =0a(4) =60a(5) =900a(6) =8400a(7) =63000a(8) =417120a(9) =2551560a(10) =14804700a(11) =82764900a(12) =450518460a(13) =2404510500a(14) =12646078200a(15) =65771496000a(16) =339165516120

External references