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A237562
Number of (n+1)X(3+1) 0..2 arrays with the upper median plus the lower median of every 2X2 subblock differing from its horizontal and vertical neighbors by exactly one
1
1256, 7356, 44828, 272828, 1668300, 10006572, 61521086, 369916012, 2269219612, 13640047444, 83744336902, 503289951172, 3089491881388, 18568951596028, 113990187566058, 685097693973988, 4205677467677088, 25276889819728684
OFFSET
1,1
COMMENTS
Column 3 of A237567
LINKS
FORMULA
Empirical: a(n) = 16*a(n-2) +835*a(n-4) +3123*a(n-6) -159248*a(n-8) -1813163*a(n-10) +3420332*a(n-12) +152514352*a(n-14) +758178885*a(n-16) -54193399*a(n-18) -7796952237*a(n-20) -1698826988*a(n-22) +55481380191*a(n-24) -33638247889*a(n-26) -251552367009*a(n-28) +641441995116*a(n-30) +1246987460767*a(n-32) -1248644036925*a(n-34) -299948298657*a(n-36) +2560742766617*a(n-38) +1285778974330*a(n-40) +3182913517154*a(n-42) -8663654405072*a(n-44) -13182084846408*a(n-46) +11771304105080*a(n-48) -1612030103286*a(n-50) -516148288180*a(n-52) +132591788800*a(n-54) +18319631360*a(n-56) +833992704*a(n-58) -26394624*a(n-60) for n>63
EXAMPLE
Some solutions for n=3
..2..1..2..2....2..0..0..0....1..0..1..1....0..2..0..1....1..2..1..1
..2..0..1..0....1..0..1..1....1..2..0..2....1..0..2..2....2..2..1..0
..0..2..2..1....1..2..0..2....2..0..2..1....1..1..2..1....1..1..0..1
..1..2..0..2....2..0..2..1....1..1..0..1....2..2..2..0....2..1..0..0
CROSSREFS
Sequence in context: A280928 A080718 A219993 * A304829 A216941 A159726
KEYWORD
nonn
AUTHOR
R. H. Hardin, Feb 09 2014
STATUS
approved