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!)
A258891 Number of (n+2) X (5+2) 0..1 arrays with no 3 x 3 subblock diagonal sum less than the antidiagonal sum or central row sum less than the central column sum. 1
30870, 23409, 12804, 9604, 12544, 16384, 21320, 27556, 35360, 44944, 56680, 70756, 87680, 107584, 131144, 158404, 190240, 226576, 268520, 315844, 369920, 430336, 498760, 574564, 659744, 753424, 857960, 972196, 1098880, 1236544, 1388360 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
FORMULA
Empirical: a(n) = 2*a(n-1) + 2*a(n-2) - 6*a(n-3) + 6*a(n-5) - 2*a(n-6) - 2*a(n-7) + a(n-8) for n>11.
Empirical for n mod 2 = 0: a(n) = n^4 + 10*n^3 + 149*n^2 + 620*n + 3844 for n>3.
Empirical for n mod 2 = 1: a(n) = n^4 + 10*n^3 + 150*n^2 + 610*n + 3869 for n>3.
Empirical g.f.: x*(30870 - 38331*x - 95754*x^2 + 122398*x^3 + 108182*x^4 - 136308*x^5 - 57626*x^6 + 59146*x^7 + 19844*x^8 - 6825*x^9 - 5404*x^10) / ((1 - x)^5*(1 + x)^3). - Colin Barker, Dec 23 2018
EXAMPLE
Some solutions for n=4:
..1..0..0..0..0..0..0....1..1..0..0..0..0..0....1..1..0..1..0..0..1
..0..0..0..0..0..0..0....1..1..0..1..0..1..0....1..0..1..0..1..0..0
..0..0..0..0..0..0..0....1..0..1..0..1..0..1....1..1..0..1..0..1..1
..0..0..0..0..0..0..1....1..1..0..1..0..1..0....1..0..1..0..1..0..1
..0..0..0..0..0..0..1....1..0..1..0..1..0..1....1..1..0..1..0..1..1
..0..0..0..0..0..0..1....1..1..0..1..0..1..0....0..0..1..0..1..1..1
CROSSREFS
Column 5 of A258894.
Sequence in context: A269828 A270057 A236899 * A237469 A071124 A250590
KEYWORD
nonn
AUTHOR
R. H. Hardin, Jun 14 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 March 2 21:56 EST 2024. Contains 370498 sequences. (Running on oeis4.)