Number of pairs of cycles of cardinality at least 2.

A052518

Number of pairs of cycles of cardinality at least 2.

Terms

    a(0) =0a(1) =0a(2) =0a(3) =0a(4) =6a(5) =40a(6) =260a(7) =1848a(8) =14616a(9) =128448a(10) =1246752a(11) =13273920a(12) =153996480a(13) =1935048960a(14) =26193473280a(15) =380120670720

External references