A195250 Number of lower triangles of a 4X4 0..n array with each element differing from all of its diagonal, vertical, antidiagonal and horizontal neighbors by two or less.
1024, 59049, 190514, 357847, 533142, 709613, 886084, 1062555, 1239026, 1415497, 1591968, 1768439, 1944910, 2121381, 2297852, 2474323, 2650794, 2827265, 3003736, 3180207, 3356678, 3533149, 3709620, 3886091, 4062562, 4239033, 4415504, 4591975
Offset: 1
Keywords
Examples
Some solutions for n=5 ..2........5........3........0........5........1........2........3 ..0.0......4.3......2.1......0.2......5.5......0.0......0.2......1.2 ..1.2.1....4.3.1....0.2.2....0.1.3....5.5.3....0.2.1....1.1.1....2.0.2 ..2.1.3.2..3.3.1.0..1.0.1.2..0.2.2.2..4.4.5.4..0.1.0.0..2.0.1.2..2.0.1.0
Links
- R. H. Hardin, Table of n, a(n) for n = 1..200
Formula
Empirical: a(n) = 176471*n - 349213 for n>4
Comments