A194540 T(n,k) is the number of lower triangles of an n X n 0..k array with new values introduced in row major order 0..k and no element equal to more than one horizontal or vertical neighbor.
1, 1, 3, 1, 4, 6, 1, 4, 59, 12, 1, 4, 116, 1851, 23, 1, 4, 131, 16556, 119548, 43, 1, 4, 132, 43785, 7721920, 16039294, 79, 1, 4, 132, 62038, 79201795, 11525456507, 4460214471, 143, 1, 4, 132, 67377, 286773762, 627974590650, 54979732214116, 2572187445993
Offset: 1
Examples
Table starts: ...1.............1..................1......................1 ...3.............4..................4......................4 ...6............59................116....................131 ..12..........1851..............16556..................43785 ..23........119548............7721920...............79201795 ..43......16039294........11525456507...........627974590650 ..79....4460214471.....54979732214116......21399815343394998 .143.2572187445993.838387866908847478.3132305932642809585983 Some solutions for n=4 and k=3: ..0........0........0........0........0........0........0........0 ..1.2......1.0......1.0......1.0......0.1......1.2......1.0......1.2 ..3.1.1....0.1.0....2.0.3....2.3.1....2.3.0....1.3.3....2.3.3....0.3.1 ..2.3.2.0..2.1.3.1..2.1.0.1..1.0.3.2..3.0.3.1..3.1.1.2..0.2.2.0..2.1.2.1
Links
- R. H. Hardin, Table of n, a(n) for n = 1..86
Crossrefs
Column 1 is A055244.