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A253325
Number of (n+1)X(7+1) 0..1 arrays with every 2X2 subblock sum nondecreasing horizontally, vertically and antidiagonally ne-to-sw
1
3249, 17197, 86922, 185672, 503944, 797324, 1660088, 2516513, 4869987, 7734273, 14919670, 25495092, 49930717, 90999544, 180464019, 343236331, 684939660, 1334617667, 2669247347, 5267675675, 10540870453, 20938024856, 41896374843
OFFSET
1,1
COMMENTS
Column 7 of A253326
LINKS
FORMULA
Empirical: a(n) = 4*a(n-1) +2*a(n-2) -26*a(n-3) +16*a(n-4) +62*a(n-5) -70*a(n-6) -62*a(n-7) +109*a(n-8) +14*a(n-9) -76*a(n-10) +16*a(n-11) +20*a(n-12) -8*a(n-13) for n>26
EXAMPLE
Some solutions for n=4
..0..0..1..0..0..0..0..0....0..0..0..0..0..0..0..0....0..0..1..0..0..0..0..0
..1..0..0..0..1..0..1..0....0..0..0..0..0..1..0..1....1..0..0..0..1..0..1..0
..0..0..1..0..1..0..1..0....0..0..0..1..0..0..1..0....0..0..1..0..0..1..0..1
..1..0..0..1..0..1..1..1....0..1..1..0..1..1..1..1....1..1..0..1..1..0..1..0
..0..1..1..0..1..1..1..1....1..0..0..1..0..1..1..1....0..0..1..0..0..1..0..1
CROSSREFS
Sequence in context: A265198 A269061 A253332 * A204038 A235412 A048421
KEYWORD
nonn
AUTHOR
R. H. Hardin, Dec 30 2014
STATUS
approved