A231663 - OEIS

A231663

T(n,k)=Number of nXk 0..2 arrays with no element less than a strict majority of its horizontal, vertical and antidiagonal neighbors

3, 3, 3, 9, 15, 9, 22, 93, 93, 22, 51, 458, 1197, 458, 51, 121, 2163, 13434, 13434, 2163, 121, 292, 10789, 144465, 345519, 144465, 10789, 292, 704, 53813, 1607589, 8300390, 8300390, 1607589, 53813, 704, 1691, 265397, 17962078, 206363144, 434469343

(list; table; graph; refs; listen; history; text; internal format)

OFFSET

1,1

COMMENTS

Table starts

....3.......3..........9............22...............51.................121

....3......15.........93...........458.............2163...............10789

....9......93.......1197.........13434...........144465.............1607589

...22.....458......13434........345519..........8300390...........206363144

...51....2163.....144465.......8300390........434469343.........23632808750

..121...10789....1607589.....206363144......23632808750.......2825994465190

..292...53813...17962078....5175246459....1304771142134.....344368908016123

..704..265397..199451319..128866716238...71426776678405...41555342706134920

.1691.1311447.2215334132.3207643017150.3902799543486962.5000894272327355414

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..161

FORMULA

Empirical for column k:

k=1: a(n) = 3*a(n-1) -3*a(n-2) +4*a(n-3) -a(n-4) +a(n-5) for n>6

k=2: [order 15]

k=3: [order 57]

EXAMPLE

Some solutions for n=3 k=4

..0..0..0..2....2..1..0..0....0..0..1..1....0..0..1..0....1..1..0..2

..0..2..0..0....1..1..0..0....0..0..1..0....0..0..0..0....1..0..0..1

..2..2..0..2....2..2..0..2....1..0..0..0....0..0..1..0....2..0..1..1

CROSSREFS

Column 1 is A202882 for n>1

Sequence in context: A188344 A217457 A231753 * A180439 A298315 A299189

Adjacent sequences: A231660 A231661 A231662 * A231664 A231665 A231666

KEYWORD

nonn,tabl

AUTHOR

R. H. Hardin, Nov 12 2013

STATUS

approved