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A254492 Number of (2+2)X(n+2) 0..1 arrays with every 3X3 subblock diagonal maximum plus antidiagonal minimum nondecreasing horizontally, vertically and ne-to-sw antidiagonally 1
3264, 29952, 278848, 2523008, 21822912, 186999040, 1608739904, 13816488064, 118589929664, 1017853382144, 8730146521920, 74873174657408, 642262262295488, 5509342624658176, 47257830100308544, 405368993958554240 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Row 2 of A254491

LINKS

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

FORMULA

Empirical: a(n) = 14*a(n-1) -46*a(n-2) -42*a(n-3) +624*a(n-4) -4070*a(n-5) +23726*a(n-6) -143310*a(n-7) +364913*a(n-8) +1129936*a(n-9) -6925152*a(n-10) +15765760*a(n-11) -48494080*a(n-12) +157092864*a(n-13) -333556224*a(n-14) +23502848*a(n-15) +1872896000*a(n-16) -4361814016*a(n-17) +12360941568*a(n-18) -45439909888*a(n-19) +98790080512*a(n-20) -104990769152*a(n-21) -49694113792*a(n-22) +350694146048*a(n-23) -1042871746560*a(n-24) +3605625044992*a(n-25) -7769595838464*a(n-26) +8796093022208*a(n-27) -4947802324992*a(n-28) +1099511627776*a(n-29)

EXAMPLE

Some solutions for n=2

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

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

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

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

CROSSREFS

Sequence in context: A251919 A338071 A234653 * A254485 A253857 A337792

Adjacent sequences:  A254489 A254490 A254491 * A254493 A254494 A254495

KEYWORD

nonn

AUTHOR

R. H. Hardin, Jan 31 2015

STATUS

approved

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Last modified September 27 22:01 EDT 2022. Contains 357063 sequences. (Running on oeis4.)