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A253507 Number of (n+2) X (5+2) 0..1 arrays with every 2 X 2 and 3 X 3 subblock diagonal maximum minus antidiagonal minimum nondecreasing horizontally and vertically. 1
884, 1712, 3052, 5136, 7948, 11740, 16592, 22720, 30300, 39560, 50740, 64104, 79936, 98540, 120240, 145380, 174324, 207456, 245180, 287920, 336120, 390244, 450776, 518220, 593100, 675960, 767364, 867896, 978160, 1098780, 1230400, 1373684 (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) = (5/6)*n^4 + 9*n^3 + (1135/6)*n^2 + 361*n - 300 for n>8.

Conjectures from Colin Barker, Dec 17 2018: (Start)

G.f.: 4*x*(221 - 677*x + 833*x^2 - 461*x^3 + 22*x^4 + 129*x^5 - 110*x^6 + 77*x^7 - 44*x^8 + 23*x^9 - 10*x^10 + 3*x^11 - x^12) / (1 - x)^5.

a(n) = 5*a(n-1) - 10*a(n-2) + 10*a(n-3) - 5*a(n-4) + a(n-5) for n>13.

(End)

EXAMPLE

Some solutions for n=4:

..1..1..1..1..1..1..1....0..1..1..1..1..1..1....0..1..1..1..1..1..1

..1..1..1..1..1..1..1....1..1..1..1..1..1..1....1..1..1..1..0..0..0

..1..1..1..1..1..1..1....1..1..1..1..1..0..1....1..1..1..1..1..1..1

..1..1..1..1..1..1..0....1..1..1..1..1..0..1....1..1..1..0..0..0..0

..1..1..1..1..1..1..1....1..1..1..1..1..0..1....1..1..1..1..1..1..1

..1..1..1..0..0..0..0....0..0..0..0..1..0..1....1..1..0..0..0..0..0

CROSSREFS

Column 5 of A253510.

Sequence in context: A206964 A209089 A207131 * A282156 A318200 A295443

Adjacent sequences:  A253504 A253505 A253506 * A253508 A253509 A253510

KEYWORD

nonn

AUTHOR

R. H. Hardin, Jan 02 2015

STATUS

approved

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Last modified August 19 23:59 EDT 2022. Contains 356231 sequences. (Running on oeis4.)