A235981 T(n,k)=Number of (n+1)X(k+1) 0..2 arrays with the upper median equal to the lower median in every 2X2 subblock

39, 181, 181, 815, 1473, 815, 3741, 11239, 11239, 3741, 16999, 89555, 143183, 89555, 16999, 77701, 703565, 1947197, 1947197, 703565, 77701, 354015, 5579529, 26090277, 46727365, 26090277, 5579529, 354015, 1615917, 44112111, 354374671, 1101519021

Offset

1,1

Comments

Table starts

.......39.........181............815.............3741...............16999

......181........1473..........11239............89555..............703565

......815.......11239.........143183..........1947197............26090277

.....3741.......89555........1947197.........46727365..........1101519021

....16999......703565.......26090277.......1101519021.........45610599689

....77701.....5579529......354374671......26513929449.......1940827721603

...354015....44112111.....4798700327.....636000634655......82270776987717

..1615917...349456139....65170792525...15322368309233....3506876818446715

..7368343..2766556005...884485021717..368889441554023..149366054184193657

.33618069.21911565169.12011793919475.8889119296332995.6369053509470841885

Links

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

Formula

Empirical for column k:

k=1: a(n) = 4*a(n-1) +7*a(n-2) -22*a(n-3) +8*a(n-4)

k=2: [order 9]

k=3: [order 22]

k=4: [order 61]

Example

Some solutions for n=3 k=4
..0..0..0..0..1....0..0..1..0..0....0..0..0..1..0....0..0..0..0..0
..0..0..0..1..1....0..0..0..0..1....1..0..1..1..2....0..2..0..1..0
..0..0..1..1..0....1..0..0..1..1....0..0..0..2..2....0..0..0..0..0
..0..1..2..1..2....0..0..0..0..2....0..0..2..2..0....0..0..2..0..2

Crossrefs

Sequence in context: A105838 A251335 A251328 * A235974 A258095 A193228

Adjacent sequences: A235978 A235979 A235980 * A235982 A235983 A235984

Keyword

nonn,tabl

Author

R. H. Hardin, Jan 17 2014

Status

approved