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

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 56th year, we are closing in on 350,000 sequences, and we’ve crossed 9,700 citations (which often say “discovered thanks to the OEIS”).

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A253439 Number of (5+1) X (n+1) 0..1 arrays with every 2 X 2 subblock diagonal minus antidiagonal sum nondecreasing horizontally, vertically and ne-to-sw antidiagonally. 1
 181, 180, 193, 228, 300, 444, 732, 1308, 2460, 4764, 9372, 18588, 37020, 73884, 147612, 295068, 589980, 1179804, 2359452, 4718748, 9437340, 18874524, 37748892, 75497628, 150995100, 301990044, 603979932, 1207959708, 2415919260, 4831838364 (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) = 3*a(n-1) - 2*a(n-2) for n>5. Empirical: a(n) = 9*2^(n-1) + 156 for n>3. Empirical g.f.: x*(181 - 363*x + 15*x^2 + 9*x^3 + 2*x^4) / ((1 - x)*(1 - 2*x)). - Colin Barker, Dec 12 2018 EXAMPLE Some solutions for n=4: ..1..1..1..1..1....1..1..0..0..0....0..0..0..1..0....1..0..1..1..1 ..1..1..1..1..1....1..1..0..0..0....1..0..0..1..0....1..0..1..1..1 ..0..0..0..0..0....1..1..0..0..0....1..0..0..1..0....1..0..1..1..1 ..1..1..1..1..1....1..1..0..0..0....1..0..0..1..0....1..0..1..1..1 ..0..0..0..0..0....1..1..0..0..0....1..0..0..1..0....1..0..1..1..1 ..1..1..1..1..1....1..1..0..0..1....1..0..0..1..1....1..0..1..1..1 CROSSREFS Row 5 of A253435. Sequence in context: A036200 A253432 A218977 * A175789 A157747 A253156 Adjacent sequences:  A253436 A253437 A253438 * A253440 A253441 A253442 KEYWORD nonn AUTHOR R. H. Hardin, Dec 31 2014 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.

Last modified December 5 17:28 EST 2021. Contains 349557 sequences. (Running on oeis4.)