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A256815
Number of length n+7 0..1 arrays with at most two downsteps in every 7 consecutive neighbor pairs
1
219, 402, 753, 1424, 2693, 5088, 9613, 18104, 34013, 63928, 120362, 226816, 427341, 804974, 1516179, 2855304, 5376354, 10123582, 19065294, 35907400, 67626166, 127359488, 239852341, 451704432, 850669960, 1602023036, 3017039568
OFFSET
1,1
COMMENTS
Column 7 of A256816
LINKS
FORMULA
Empirical: a(n) = 2*a(n-1) -a(n-2) +3*a(n-4) -2*a(n-5) +10*a(n-7) -7*a(n-8) -12*a(n-11) +9*a(n-12) -24*a(n-14) +18*a(n-15)
EXAMPLE
Some solutions for n=4
..1....0....1....1....0....0....0....1....1....1....1....1....0....0....0....0
..0....0....1....1....0....0....1....1....1....1....1....0....1....1....1....0
..1....0....1....1....1....1....0....1....1....1....0....1....0....1....1....0
..1....0....0....1....1....1....0....1....0....0....1....0....0....1....1....1
..0....1....1....1....0....1....0....0....0....0....0....0....0....1....1....0
..0....1....0....0....1....0....1....0....1....0....0....0....1....0....0....1
..0....0....0....0....1....0....0....0....0....1....1....1....1....0....1....1
..1....1....0....1....0....0....1....0....0....0....1....1....1....1....1....1
..1....1....0....0....1....0....1....1....0....1....1....0....1....1....0....0
..1....0....0....0....1....1....1....1....0....1....1....0....0....0....0....0
..1....0....0....1....1....0....1....1....0....1....0....1....0....0....0....0
CROSSREFS
Sequence in context: A025404 A361343 A192086 * A179580 A043435 A166836
KEYWORD
nonn
AUTHOR
R. H. Hardin, Apr 10 2015
STATUS
approved