Triangle T(n,k) of number of minimal 4-covers of a labeled n-set that cover k points of that set uniquely (k=4,..,n).

A057965

Triangle T(n,k) of number of minimal 4-covers of a labeled n-set that cover k points of that set uniquely (k=4,..,n).

Terms

    a(0) =1a(1) =55a(2) =10a(3) =1815a(4) =660a(5) =65a(6) =46585a(7) =25410a(8) =5005a(9) =350a(10) =1024870a(11) =745360a(12) =220220a(13) =30800a(14) =1701a(15) =20292426a(16) =18447660a(17) =7267260a(18) =1524600a(19) =168399a(20) =7770a(21) =372027810a(22) =405848520a(23) =199849650a(24) =55902000a(25) =9261945a(26) =854700a(27) =34105a(28) =6430766430

External references