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A207707
Number of 6Xn 0..1 arrays avoiding 0 0 0 and 0 1 0 horizontally and 0 0 1 and 1 1 0 vertically
1
12, 144, 636, 2809, 17225, 105625, 571350, 3090564, 17518470, 99301225, 552967815, 3079251081, 17262695190, 96776988100, 541164386750, 3026121180625, 16938024328125, 94806734765625, 530464911052500, 2968069964160016
OFFSET
1,1
COMMENTS
Row 6 of A207703
LINKS
FORMULA
Empirical: a(n) = 4*a(n-1) +34*a(n-3) +161*a(n-4) -304*a(n-5) -204*a(n-6) -1251*a(n-7) -5160*a(n-8) +6981*a(n-9) +6282*a(n-10) +13350*a(n-11) +58402*a(n-12) -65494*a(n-13) -61813*a(n-14) -51552*a(n-15) -279939*a(n-16) +272064*a(n-17) +231886*a(n-18) +79582*a(n-19) +630877*a(n-20) -535169*a(n-21) -359358*a(n-22) -63604*a(n-23) -717591*a(n-24) +534618*a(n-25) +255654*a(n-26) +34999*a(n-27) +423821*a(n-28) -280955*a(n-29) -93514*a(n-30) -10508*a(n-31) -135019*a(n-32) +81624*a(n-33) +18556*a(n-34) +1525*a(n-35) +23768*a(n-36) -13393*a(n-37) -1976*a(n-38) -96*a(n-39) -2276*a(n-40) +1216*a(n-41) +103*a(n-42) +2*a(n-43) +109*a(n-44) -56*a(n-45) -2*a(n-46) -2*a(n-48) +a(n-49)
EXAMPLE
Some solutions for n=4
..0..0..1..1....1..0..0..1....1..0..0..1....1..0..0..1....0..0..1..1
..1..1..0..0....0..1..1..0....0..1..1..1....1..1..0..1....0..1..1..0
..0..0..1..1....1..1..0..1....0..1..1..1....1..0..0..1....0..1..1..1
..1..0..0..1....0..1..1..0....0..1..1..1....1..1..0..1....0..1..1..0
..0..0..1..1....1..1..1..0....0..1..1..1....1..1..0..1....0..1..1..1
..1..0..1..1....0..1..1..0....0..1..1..1....1..1..0..1....0..1..1..0
CROSSREFS
Sequence in context: A209653 A207073 A207406 * A207252 A208290 A208139
KEYWORD
nonn
AUTHOR
R. H. Hardin Feb 19 2012
STATUS
approved