Given n colors, sequence gives number of ways to color the vertices of a square such that no edge has the same color on both of its vertices.

A091940

Given n colors, sequence gives number of ways to color the vertices of a square such that no edge has the same color on both of its vertices.

Terms

    a(0) =0a(1) =2a(2) =18a(3) =84a(4) =260a(5) =630a(6) =1302a(7) =2408a(8) =4104a(9) =6570a(10) =10010a(11) =14652a(12) =20748a(13) =28574a(14) =38430a(15) =50640a(16) =65552a(17) =83538a(18) =104994a(19) =130340a(20) =160020a(21) =194502a(22) =234278a(23) =279864a(24) =331800a(25) =390650a(26) =457002a(27) =531468a(28) =614684a(29) =707310

External references