A194784 Number of lower triangles of a (2n+4)X(2n+4) 0..n array with new values introduced in row major order 0..n and no element unequal to more than one horizontal or vertical neighbor.
43, 493, 4069, 30608, 229869, 1782111, 14399939, 121414559, 1066897441, 9753094999, 92586232382, 911156698994
Offset: 1
Keywords
Examples
Some solutions for n=2 containing a 2 ..0................0................0................0 ..1.1..............0.0..............1.1..............0.0 ..1.1.1............0.0.0............1.1.1............0.0.0 ..1.1.1.1..........1.1.1.1..........2.2.2.2..........1.1.1.1 ..1.1.1.1.1........1.1.1.1.1........2.2.2.2.0........1.1.1.1.0 ..1.1.1.1.1.1......2.2.2.2.2.2......2.2.2.2.0.0......1.1.1.1.0.0 ..1.1.1.1.1.1.1....2.2.2.2.2.2.2....2.2.2.2.0.0.0....1.1.1.1.0.0.2 ..1.1.1.1.1.1.1.2..2.2.2.2.2.2.2.2..2.2.2.2.0.0.0.2..1.1.1.1.0.0.2.2
Comments