A236523 - OEIS

A236523

T(n,k)=Number of (n+1)X(k+1) 0..1 arrays with the difference of the upper median and minimum value of each 2X2 subblock in lexicographically nondecreasing order columnwise and nonincreasing rowwise

16, 52, 52, 160, 264, 160, 476, 1256, 1256, 476, 1392, 5670, 9212, 5670, 1392, 4020, 25023, 63208, 63208, 25023, 4020, 11520, 108214, 421516, 655460, 421516, 108214, 11520, 32828, 462970, 2728079, 6591144, 6591144, 2728079, 462970, 32828, 93200

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

OFFSET

1,1

COMMENTS

Table starts

.....16.......52........160..........476...........1392.............4020

.....52......264.......1256.........5670..........25023...........108214

....160.....1256.......9212........63208.........421516..........2728079

....476.....5670......63208.......655460........6591144.........63997604

...1392....25023.....421516......6591144.......99655626.......1448355717

...4020...108214....2728079.....63997604.....1448355717......31459840764

..11520...462970...17385844....610630403....20627269098.....668463714817

..32828..1962897..109182283...5723134951...287546676233...13878535769685

..93200..8278491..680017778..53126385011..3961701125458..284431385172713

.263892.34768983.4204683204.488732268982.53967671743495.5756312538787583

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..162

FORMULA

Empirical for column k:

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

k=2: [order 15]

k=3: [order 37]

k=4: [order 82]

EXAMPLE

Some solutions for n=3 k=4

..1..1..0..1..0....1..0..1..0..0....0..1..1..0..1....0..0..0..1..0

..0..0..1..0..1....0..1..1..1..1....0..1..0..1..0....1..1..1..1..1

..0..0..0..1..0....1..0..1..0..1....1..0..1..1..0....1..0..1..0..1

..0..0..0..1..1....0..1..0..1..0....0..1..0..1..0....1..1..1..1..1

CROSSREFS

Column 1 is A235653

Sequence in context: A192248 A363350 A297640 * A235660 A044118 A044499

Adjacent sequences: A236520 A236521 A236522 * A236524 A236525 A236526

KEYWORD

nonn,tabl

AUTHOR

R. H. Hardin, Jan 27 2014

STATUS

approved