A254253 - OEIS

A254253

Number of (n+2)X(1+2) 0..1 arrays with every 3X3 subblock sum of the two maximums of the diagonal and antidiagonal minus the sum of the minimums of the central row and column nondecreasing horizontally, vertically and ne-to-sw antidiagonally.

512, 2812, 12616, 54236, 236024, 1021428, 4351908, 18369164, 77344420, 325241108, 1364914276, 5718111752, 23932201612, 100109932552, 418582178324, 1749544313608, 7310677021040, 30543411626736, 127592728853128

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OFFSET

1,1

COMMENTS

Column 1 of A254260

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..210

FORMULA

Empirical: a(n) = 7*a(n-1) -13*a(n-2) +11*a(n-3) -13*a(n-4) -60*a(n-5) -32*a(n-6) +210*a(n-7) +501*a(n-8) -221*a(n-9) +109*a(n-10) -981*a(n-11) -1875*a(n-12) +1430*a(n-13) +856*a(n-14) -180*a(n-15) +468*a(n-16) -216*a(n-17)

EXAMPLE

Some solutions for n=4

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

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

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

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

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

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

CROSSREFS

Sequence in context: A254306 A258530 A254922 * A254915 A257154 A254743

Adjacent sequences: A254250 A254251 A254252 * A254254 A254255 A254256

KEYWORD

nonn

AUTHOR

R. H. Hardin, Jan 27 2015

STATUS

approved