Number of nX2 0..4 arrays with rows and columns lexicographically nondecreasing and no element equal to the number of horizontal and vertical neighbors equal to itself.
A201723
Number of nX2 0..4 arrays with rows and columns lexicographically nondecreasing and no element equal to the number of horizontal and vertical neighbors equal to itself.
Terms
- a(0) =10a(1) =90a(2) =631a(3) =3567a(4) =16493a(5) =64018a(6) =213013a(7) =621757a(8) =1626046a(9) =3878550a(10) =8560638a(11) =17688966a(12) =34541082a(13) =64226182a(14) =114429139a(15) =196357695a(16) =325924563a(17) =525198174a(18) =824157734a(19) =1262790173a(20) =1893568514a(21) =2784353134a(22) =4021759333a(23) =5715036571
External references
- oeis: A201723