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A220456 Equals one maps: number of nX2 binary arrays indicating the locations of corresponding elements equal to exactly one of their horizontal, vertical and antidiagonal neighbors in a random 0..1 nX2 array 1
2, 4, 22, 74, 250, 848, 2851, 9535, 31888, 106775, 357028, 1193927, 3992279, 13348541, 44630321, 149215567, 498878032, 1667898396, 5576255601, 18642932177, 62328230082, 208379401186, 696665636518, 2329130179184, 7786871066006 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
Column 2 of A220461
LINKS
FORMULA
Empirical: a(n) = 6*a(n-1) -11*a(n-2) +10*a(n-3) -11*a(n-4) +7*a(n-5) -22*a(n-6) +61*a(n-7) -101*a(n-8) +159*a(n-9) -166*a(n-10) +159*a(n-11) -137*a(n-12) +189*a(n-13) -246*a(n-14) +239*a(n-15) -183*a(n-16) +96*a(n-17) -60*a(n-18) +193*a(n-19) -214*a(n-20) +187*a(n-21) -199*a(n-22) +29*a(n-23) -105*a(n-24) +20*a(n-25) -37*a(n-26) +13*a(n-27) -8*a(n-28) +4*a(n-29) for n>34
EXAMPLE
Some solutions for n=3
..1..1....0..0....1..0....1..1....0..0....1..0....0..1....0..0....1..1....1..0
..0..1....0..1....1..0....1..1....0..0....0..1....1..1....0..0....0..0....0..0
..0..1....1..0....1..1....1..1....0..0....1..1....1..0....0..1....0..0....1..0
CROSSREFS
Sequence in context: A134246 A254867 A305492 * A071298 A152104 A047035
KEYWORD
nonn
AUTHOR
R. H. Hardin Dec 15 2012
STATUS
approved

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Last modified March 4 23:31 EST 2024. Contains 370537 sequences. (Running on oeis4.)