cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A231219 T(n,k)=Number of (n+1)X(k+1) 0..2 arrays with no element unequal to a strict majority of its horizontal and vertical neighbors, with values 0..2 introduced in row major order.

Original entry on oeis.org

3, 4, 4, 7, 9, 7, 12, 22, 22, 12, 23, 59, 93, 59, 23, 44, 156, 408, 408, 156, 44, 87, 413, 1793, 2892, 1793, 413, 87, 172, 1098, 7844, 20027, 20027, 7844, 1098, 172, 343, 2919, 34609, 139438, 226764, 139438, 34609, 2919, 343, 684, 7760, 152421, 969461
Offset: 1

Views

Author

R. H. Hardin, Nov 05 2013

Keywords

Comments

Table starts
...3.....4.......7........12..........23............44.............87
...4.....9......22........59.........156...........413...........1098
...7....22......93.......408........1793..........7844..........34609
..12....59.....408......2892.......20027........139438.........969461
..23...156....1793.....20027......226764.......2534951.......28439115
..44...413....7844....139438.....2534951......45593903......820418528
..87..1098...34609....969461....28439115.....820418528....23748656906
.172..2919..152421...6745110...318236849...14743946094...685733582035
.343..7760..672446..46938804..3565691309..265057746273.19812622781057
.684.20633.2965705.326645650.39935313475.4764850607558

Examples

			Some solutions for n=4 k=4
..0..0..0..1..1....0..0..0..0..0....0..0..0..0..0....0..0..1..1..0
..0..0..0..1..1....1..1..1..1..1....1..1..1..2..2....0..0..1..1..0
..0..0..0..2..2....1..0..0..0..1....1..1..1..2..2....0..0..1..1..0
..0..0..0..2..2....1..0..0..0..1....1..1..1..2..2....0..0..1..1..0
..2..2..2..2..2....1..1..1..1..1....1..1..1..2..2....0..0..1..1..0
		

Crossrefs

Column 1 is A023105(n+2)

Formula

Empirical for column k:
k=1: a(n) = 2*a(n-1) +a(n-2) -2*a(n-3)
k=2: a(n) = 3*a(n-1) -a(n-2) +a(n-3) -2*a(n-4)
k=3: [order 19]
k=4: [order 68]