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!)
A234680 Number of (n+1) X (7+1) 0..5 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
164416, 243164, 354856, 639440, 1109272, 2354408, 4736536, 11294552, 25494136, 66161144, 162985816, 451913720, 1189756792, 3483132728, 9648855256, 29560946552, 85169950456, 270999391544, 804887071576, 2641964987000 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..29

FORMULA

Empirical: a(n) = 4*a(n-1) +47*a(n-2) -200*a(n-3) -901*a(n-4) +4204*a(n-5) +8957*a(n-6) -48440*a(n-7) -47194*a(n-8) +334096*a(n-9) +101948*a(n-10) -1410080*a(n-11) +170136*a(n-12) +3549696*a(n-13) -1446912*a(n-14) -4861440*a(n-15) +2954880*a(n-16) +2764800*a(n-17) -2073600*a(n-18).

EXAMPLE

Some solutions for n=1:

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

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

CROSSREFS

Column 7 of A234681.

Sequence in context: A110072 A196675 A034603 * A226004 A233705 A233706

Adjacent sequences:  A234677 A234678 A234679 * A234681 A234682 A234683

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 October 3 02:59 EDT 2022. Contains 357230 sequences. (Running on oeis4.)