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!)
A234684 Number of (n+1) X (2+1) 0..6 arrays with every 2 X 2 subblock having its diagonal sum differing from its antidiagonal sum by 5 (constant-stress 1 X 1 tilings). 1
1148, 4416, 16580, 69336, 281612, 1253088, 5385236, 25119456, 112545548, 544181136, 2514628340, 12495760896, 59077785452, 299739293328, 1441310414996, 7429688790336, 36177693563468, 188779231755216, 927888726542900 (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) = 7*a(n-1) +136*a(n-2) -1036*a(n-3) -7837*a(n-4) +67291*a(n-5) +245614*a(n-6) -2526790*a(n-7) -4355332*a(n-8) +60808804*a(n-9) +36086728*a(n-10) -982312744*a(n-11) +135510432*a(n-12) +10839179904*a(n-13) -6945594624*a(n-14) -81450996480*a(n-15) +81465827328*a(n-16) +407151166464*a(n-17) -514409232384*a(n-18) -1284949370880*a(n-19) +1874710241280*a(n-20) +2296420761600*a(n-21) -3685898649600*a(n-22) -1755758592000*a(n-23) +3009871872000*a(n-24).

EXAMPLE

Some solutions for n=4:

  1 1 2   5 1 0   1 5 2   4 4 4   6 6 6   5 1 5   0 4 4

  5 0 6   0 1 5   5 4 6   6 1 6   6 1 6   5 6 5   6 5 0

  2 2 3   0 6 5   0 4 1   2 2 2   3 3 3   0 6 0   6 0 0

  1 6 2   5 6 0   2 1 3   0 5 0   5 0 5   0 1 0   1 0 5

  2 2 3   0 6 5   1 5 2   6 6 6   5 5 5   5 1 5   1 5 5

CROSSREFS

Column 2 of A234690.

Sequence in context: A031785 A274297 A074255 * A270513 A233944 A329520

Adjacent sequences:  A234681 A234682 A234683 * A234685 A234686 A234687

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 September 25 18:27 EDT 2022. Contains 356986 sequences. (Running on oeis4.)