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A238249 Number of (n+1)X(2+1) 0..1 arrays with 2X2 subblock sums lexicographically nondecreasing columnwise and rowwise 1
44, 180, 804, 2818, 9991, 29995, 90225, 241945, 649320, 1605951, 3974215, 9269399, 21628177, 48322967, 107991481, 233776405, 506133563, 1070574873, 2264593031, 4710021487, 9796211590, 20129009598, 41359935334, 84255978136, 171637137305 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 2 of A238255

LINKS

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

FORMULA

Empirical: a(n) = 4*a(n-1) +16*a(n-2) -82*a(n-3) -99*a(n-4) +774*a(n-5) +196*a(n-6) -4456*a(n-7) +1106*a(n-8) +17464*a(n-9) -10080*a(n-10) -49212*a(n-11) +40922*a(n-12) +102532*a(n-13) -108728*a(n-14) -159592*a(n-15) +207747*a(n-16) +184428*a(n-17) -296048*a(n-18) -153442*a(n-19) +318857*a(n-20) +83878*a(n-21) -259308*a(n-22) -19872*a(n-23) +157052*a(n-24) -10232*a(n-25) -68768*a(n-26) +12128*a(n-27) +20592*a(n-28) -5472*a(n-29) -3776*a(n-30) +1280*a(n-31) +320*a(n-32) -128*a(n-33)

EXAMPLE

Some solutions for n=5

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

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

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

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

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

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

CROSSREFS

Sequence in context: A235407 A006563 A159033 * A189547 A026908 A183246

Adjacent sequences:  A238246 A238247 A238248 * A238250 A238251 A238252

KEYWORD

nonn

AUTHOR

R. H. Hardin, Feb 21 2014

STATUS

approved

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Last modified September 29 03:29 EDT 2022. Contains 357082 sequences. (Running on oeis4.)