login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A233811 Number of (n+1) X (1+1) 0..5 arrays with every 2 X 2 subblock having the sum of the squares of all six edge and diagonal differences equal to 11. 1
96, 428, 1824, 8136, 34848, 155488, 667200, 2977440, 12787200, 57068480, 245195520, 1094334720, 4702809600, 20989561600, 90210201600, 402629644800, 1730534860800, 7723826124800, 33198475776000, 148173756672000 (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) = 30*a(n-2) - 220*a(n-4) + 240*a(n-6).

Empirical g.f.: 4*x*(24 + 107*x - 264*x^2 - 1176*x^3 + 312*x^4 + 1392*x^5) / (1 - 30*x^2 + 220*x^4 - 240*x^6). - Colin Barker, Oct 11 2018

EXAMPLE

Some solutions for n=5:

..2..1....3..2....2..1....3..3....3..1....1..3....5..4....4..3....2..3....3..2

..1..3....2..4....0..2....1..2....3..2....1..2....5..3....5..5....3..1....3..1

..2..1....3..2....0..1....3..1....3..1....1..3....3..4....3..4....2..3....1..2

..1..3....1..3....0..2....1..2....2..1....3..2....2..4....2..2....1..3....3..3

..2..1....2..3....0..1....0..2....1..3....3..1....2..3....1..0....2..3....4..5

..1..3....3..1....2..0....1..2....2..3....2..3....4..4....2..0....3..1....3..5

CROSSREFS

Column 1 of A233818.

Sequence in context: A179825 A304515 A233818 * A233717 A233710 A234083

Adjacent sequences:  A233808 A233809 A233810 * A233812 A233813 A233814

KEYWORD

nonn

AUTHOR

R. H. Hardin, Dec 16 2013

STATUS

approved

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

License Agreements, Terms of Use, Privacy Policy. .

Last modified February 28 08:13 EST 2020. Contains 332321 sequences. (Running on oeis4.)