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.

A283042 T(n,k)=Number of nXk 0..1 arrays with no 1 equal to more than one of its horizontal and vertical neighbors, with the exception of exactly one element.

Original entry on oeis.org

0, 0, 0, 1, 4, 1, 2, 16, 16, 2, 5, 68, 119, 68, 5, 12, 256, 818, 818, 256, 12, 26, 924, 5065, 9152, 5065, 924, 26, 56, 3232, 30378, 94368, 94368, 30378, 3232, 56, 118, 11044, 175963, 931844, 1604067, 931844, 175963, 11044, 118, 244, 37104, 997302, 8912378
Offset: 1

Views

Author

R. H. Hardin, Feb 27 2017

Keywords

Comments

Table starts
...0......0........1..........2.............5..............12................26
...0......4.......16.........68...........256.............924..............3232
...1.....16......119........818..........5065...........30378............175963
...2.....68......818.......9152.........94368..........931844...........8912378
...5....256.....5065......94368.......1604067........26180826.........414085368
..12....924....30378.....931844......26180826.......706205768.......18455711930
..26...3232...175963....8912378.....414085368.....18455711930......797350288363
..56..11044...997302...83420984....6406597648....471954803540....33705434438284
.118..37104..5559013..767704036...97480211225..11868995624930..1401215705047092
.244.122984.30578068.6973000128.1463896864692.294610925837548.57496998569457406

Examples

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

Crossrefs

Column 1 is A073778(n-1).

Formula

Empirical for column k:
k=1: a(n) = 2*a(n-1) +a(n-2) -3*a(n-4) -2*a(n-5) -a(n-6)
k=2: a(n) = 4*a(n-1) +2*a(n-2) -12*a(n-3) -11*a(n-4) +4*a(n-5) +6*a(n-6) -a(n-8)
k=3: [order 18]
k=4: [order 30]
k=5: [order 72]