The OEIS mourns the passing of Jim Simons and is grateful to the Simons Foundation for its support of research in many branches of science, including the OEIS.
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!)
A234651 Number of (n+1) X (1+1) 0..5 arrays with every 2 X 2 subblock having its diagonal sum differing from its antidiagonal sum by 4 (constant-stress 1 X 1 tilings). 1
160, 728, 3264, 15008, 67840, 315008, 1434624, 6722048, 30822400, 145614848, 671760384, 3197247488, 14829813760, 71052197888, 331140562944, 1595912880128, 7469054033920, 36183831216128, 169965785186304, 827149902675968 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
FORMULA
Empirical: a(n) = 4*a(n-1) + 44*a(n-2) - 176*a(n-3) - 480*a(n-4) + 1920*a(n-5).
Empirical g.f.: 8*x*(20 + 11*x - 836*x^2 - 240*x^3 + 8640*x^4) / ((1 - 4*x)*(1 - 20*x^2)*(1 - 24*x^2)). - Colin Barker, Oct 15 2018
EXAMPLE
Some solutions for n=5:
5 2 4 4 2 4 5 1 0 1 1 2 2 3 5 4 2 2 1 4
4 5 4 0 3 1 1 1 5 2 4 1 4 1 0 3 1 5 2 1
5 2 5 5 2 4 4 0 1 2 1 2 2 3 1 0 2 2 1 4
0 1 0 4 4 2 1 1 5 2 3 0 4 1 2 5 0 4 5 4
5 2 1 1 0 2 4 0 0 1 3 4 1 2 5 4 5 5 0 3
1 2 1 5 2 0 4 4 0 5 0 5 3 0 5 0 0 4 4 3
CROSSREFS
Column 1 of A234658.
Sequence in context: A233917 A233910 A234658 * A234898 A234891 A305272
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 29 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 | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified May 19 07:05 EDT 2024. Contains 372666 sequences. (Running on oeis4.)