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.

A239537 T(n,k)=Number of (n+1)X(k+1) 0..2 arrays with no element equal to all horizontal neighbors or unequal to all vertical neighbors, and new values 0..2 introduced in row major order.

Original entry on oeis.org

1, 2, 1, 6, 2, 6, 16, 6, 24, 13, 44, 16, 216, 68, 47, 120, 44, 1536, 1014, 406, 128, 328, 120, 11616, 11108, 13254, 1584, 405, 896, 328, 86400, 131988, 293741, 98304, 7790, 1181, 2448, 896, 645504, 1533792, 7199001, 3785280, 984150, 33630, 3598, 6688, 2448
Offset: 1

Views

Author

R. H. Hardin, Mar 21 2014

Keywords

Comments

Table starts
.....1......2.........6...........16..............44...............120
.....1......2.........6...........16..............44...............120
.....6.....24.......216.........1536...........11616.............86400
....13.....68......1014........11108..........131988...........1533792
....47....406.....13254.......293741.........7199001.........171712936
...128...1584.....98304......3785280.......165336096........6976042240
...405...7790....984150.....71388971......5988724293......482858009716
..1181..33630...8368566...1093269814....169350916116....25030781490504
..3598.156032..77673624..18727824939...5466853947751..1514104924173186
.10705.695344.687582150.301846514891.164296850179323.84271877225127052

Examples

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

Crossrefs

Row 1 and 2 are A002605
Row 3 is A231317

Formula

Empirical for column k:
k=1: a(n) = 2*a(n-1) +4*a(n-2) -3*a(n-3)
k=2: [order 10]
k=3: a(n) = 8*a(n-1) +26*a(n-2) -166*a(n-3) +96*a(n-4) +198*a(n-5) -81*a(n-6)
Empirical for row n:
n=1: a(n) = 2*a(n-1) +2*a(n-2)
n=2: a(n) = 2*a(n-1) +2*a(n-2)
n=3: a(n) = 6*a(n-1) +12*a(n-2) -8*a(n-3)
n=4: [order 10]
n=5: [order 37]
n=6: [order 85]