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!)
A253469 Number of (n+1) X (7+1) 0..2 arrays with every 2 X 2 subblock diagonal maximum minus antidiagonal minimum unequal to its neighbors horizontally, vertically, diagonally and antidiagonally. 1
7227096, 44464, 17000, 15680, 20000, 20864, 32000, 41600, 80000, 124544, 272000, 456320, 1040000, 1783424, 4112000, 7091840, 16400000, 28325504, 65552000, 113260160, 262160000, 452998784, 1048592000, 1811953280, 4194320000 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
FORMULA
Empirical: a(n) = 5*a(n-2) - 4*a(n-4) for n>6.
Empirical g.f.: 8*x*(903387 + 5558*x - 4514810*x^2 - 25830*x^3 + 3605423*x^4 + 15040*x^5) / ((1 - x)*(1 + x)*(1 - 2*x)*(1 + 2*x)). - Colin Barker, Dec 15 2018
EXAMPLE
Some solutions for n=1:
..0..0..0..1..0..2..2..2....0..0..0..0..1..0..2..1....0..0..0..2..1..1..2..2
..1..0..1..1..0..2..0..2....2..0..2..0..2..0..2..1....2..0..1..0..2..2..1..1
CROSSREFS
Column 7 of A253468.
Sequence in context: A286010 A184214 A181680 * A325606 A157378 A251356
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jan 01 2015
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 February 25 10:05 EST 2024. Contains 370315 sequences. (Running on oeis4.)