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A235551 Number of (n+1)X(3+1) 0..1 arrays with the sum of each 2X2 subblock two extreme terms minus its two median terms lexicographically nondecreasing rowwise and columnwise 1
120, 814, 5567, 33851, 184281, 892122, 3925717, 15834473, 59506551, 209811804, 701617754, 2235893345, 6840089137, 20153696074, 57486754527, 159114503083, 428959896263, 1128320167213, 2903976632760, 7322640491124, 18130800682746 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 3 of A235555

LINKS

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

FORMULA

Empirical: a(n) = 4*a(n-1) +35*a(n-2) -158*a(n-3) -566*a(n-4) +2984*a(n-5) +5518*a(n-6) -35860*a(n-7) -34899*a(n-8) +307860*a(n-9) +134985*a(n-10) -2009442*a(n-11) -146036*a(n-12) +10361384*a(n-13) -2055944*a(n-14) -43291072*a(n-15) +17856377*a(n-16) +149141740*a(n-17) -88146091*a(n-18) -428837090*a(n-19) +320702778*a(n-20) +1037666520*a(n-21) -926474634*a(n-22) -2123839620*a(n-23) +2196630507*a(n-24) +3685625340*a(n-25) -4350171921*a(n-26) -5420700030*a(n-27) +7267723728*a(n-28) +6732949080*a(n-29) -10298203356*a(n-30) -7007379432*a(n-31) +12402868752*a(n-32) +6021828864*a(n-33) -12690037008*a(n-34) -4154733792*a(n-35) +10997624704*a(n-36) +2163244160*a(n-37) -8028312512*a(n-38) -698220160*a(n-39) +4894723328*a(n-40) -31167488*a(n-41) -2461727488*a(n-42) +213300736*a(n-43) +1003462656*a(n-44) -156899328*a(n-45) -323171328*a(n-46) +70256640*a(n-47) +79130624*a(n-48) -21463040*a(n-49) -13840384*a(n-50) +4415488*a(n-51) +1540096*a(n-52) -557056*a(n-53) -81920*a(n-54) +32768*a(n-55)

EXAMPLE

Some solutions for n=5

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

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

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

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

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

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

CROSSREFS

Sequence in context: A052627 A251264 A206025 * A300664 A029573 A211471

Adjacent sequences:  A235548 A235549 A235550 * A235552 A235553 A235554

KEYWORD

nonn

AUTHOR

R. H. Hardin, Jan 12 2014

STATUS

approved

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Last modified November 29 05:05 EST 2021. Contains 349416 sequences. (Running on oeis4.)