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.

A230652 T(n,k)=Number of nXk 0..2 white square subarrays x(i,j) with each element diagonally or antidiagonally next to at least one element with value 2-x(i,j).

Original entry on oeis.org

0, 0, 0, 0, 3, 0, 0, 3, 3, 0, 0, 9, 3, 9, 0, 0, 15, 21, 21, 15, 0, 0, 33, 27, 123, 27, 33, 0, 0, 63, 177, 531, 531, 177, 63, 0, 0, 129, 231, 2547, 1635, 2547, 231, 129, 0, 0, 255, 1509, 11745, 28161, 28161, 11745, 1509, 255, 0, 0, 513, 1971, 54957, 90393, 337977, 90393
Offset: 1

Views

Author

R. H. Hardin, Oct 27 2013

Keywords

Comments

Table starts
.0...0....0.....0.......0........0..........0...........0.............0
.0...3....3.....9......15.......33.........63.........129...........255
.0...3....3....21......27......177........231........1509..........1971
.0...9...21...123.....531.....2547......11745.......54957........255753
.0..15...27...531....1635....28161......90393.....1539207.......4956927
.0..33..177..2547...28161...337977....3951657....46564959.....547445439
.0..63..231.11745...90393..3951657...31908483..1374288243...11150938215
.0.129.1509.54957.1539207.46564959.1374288243.40860127671.1212230763441

Examples

			Some solutions for n=5 k=4
..2..x..2..x....0..x..0..x....1..x..0..x....0..x..0..x....1..x..0..x
..x..0..x..0....x..2..x..2....x..1..x..2....x..2..x..2....x..1..x..2
..0..x..2..x....0..x..1..x....1..x..1..x....0..x..0..x....1..x..0..x
..x..2..x..2....x..0..x..1....x..2..x..0....x..1..x..0....x..1..x..2
..0..x..0..x....2..x..2..x....0..x..2..x....1..x..2..x....1..x..1..x
		

Crossrefs

Column 2 is A062510(n-1)

Formula

Empirical for column k:
k=1: a(n) = a(n-1)
k=2: a(n) = a(n-1) +2*a(n-2)
k=3: a(n) = 9*a(n-2) -4*a(n-4)
k=4: a(n) = 3*a(n-1) +8*a(n-2) -a(n-3) -a(n-4) for n>5
k=5: a(n) = 59*a(n-2) -230*a(n-4) -2*a(n-6) +32*a(n-8) for n>11
k=6: [order 23] for n>24
k=7: [order 46] for n>47