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A253744 Number of (n+1)X(3+1) 0..2 arrays with every 2X2 subblock ne-sw antidiagonal difference nondecreasing horizontally and nw+se diagonal sum nondecreasing vertically 1
1998, 10182, 77414, 382973, 1636717, 5648005, 17980643, 52078415, 140931619, 357840627, 868453186, 2023764359, 4558420081, 9965846712, 21261754665, 44410393873, 91091870910, 183925891758, 366444204565, 721742419593 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 3 of A253749

LINKS

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

FORMULA

Empirical: a(n) = 7*a(n-1) -19*a(n-2) +24*a(n-3) -6*a(n-4) -41*a(n-5) +105*a(n-6) -121*a(n-7) +34*a(n-8) +108*a(n-9) -232*a(n-10) +235*a(n-11) -48*a(n-12) -163*a(n-13) +253*a(n-14) -209*a(n-15) +10*a(n-16) +148*a(n-17) -130*a(n-18) +67*a(n-19) +26*a(n-20) -79*a(n-21) +19*a(n-22) +13*a(n-23) -14*a(n-24) +24*a(n-25) -7*a(n-27) -4*a(n-28) -5*a(n-29) +7*a(n-30) -3*a(n-31) +3*a(n-32) +a(n-33) -3*a(n-34) +a(n-35) for n>45

EXAMPLE

Some solutions for n=3

..1..1..0..1....1..2..1..2....1..0..0..2....1..0..0..2....1..0..0..1

..1..0..0..2....2..0..0..1....1..0..1..1....0..0..1..1....1..0..0..0

..1..1..1..2....2..1..2..2....2..1..1..2....2..1..1..2....2..1..0..0

..1..1..1..1....2..2..1..2....2..0..1..2....1..1..0..2....2..1..1..2

CROSSREFS

Sequence in context: A296826 A171467 A258106 * A253751 A031808 A167292

Adjacent sequences:  A253741 A253742 A253743 * A253745 A253746 A253747

KEYWORD

nonn

AUTHOR

R. H. Hardin, Jan 11 2015

STATUS

approved

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Last modified June 16 19:49 EDT 2021. Contains 345068 sequences. (Running on oeis4.)