login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A237377 Number of (n+1) X (1+1) 0..2 arrays with the maximum plus the minimum minus the upper median minus the lower median of every 2 X 2 subblock differing from its horizontal and vertical neighbors by exactly one. 1
81, 344, 1472, 6368, 27280, 115584, 494592, 2139648, 9166080, 38836224, 166182912, 718921728, 3079802880, 13048971264, 55837458432, 241557700608, 1034813767680, 4384454344704, 18761386033152, 81163387404288, 347697425940480 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..210

FORMULA

Empirical: a(n) = 336*a(n-4) for n>5.

Empirical g.f.: x*(81 + 344*x + 1472*x^2 + 6368*x^3 + 64*x^4) / (1 - 336*x^4). - Colin Barker, Oct 22 2018

EXAMPLE

Some solutions for n=5:

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

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

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

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

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

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

CROSSREFS

Column 1 of A237384.

Sequence in context: A237384 A237249 A236096 * A237242 A236089 A236737

Adjacent sequences:  A237374 A237375 A237376 * A237378 A237379 A237380

KEYWORD

nonn

AUTHOR

R. H. Hardin, Feb 07 2014

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified May 20 01:04 EDT 2022. Contains 353847 sequences. (Running on oeis4.)