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A212398
Number of binary arrays of length n+7 with no more than 4 ones in any length 8 subsequence (=50% duty cycle)
1
163, 291, 527, 959, 1747, 3179, 5769, 10425, 18729, 33706, 60797, 109800, 198415, 358592, 647959, 1170415, 2113372, 3815438, 6888722, 12439093, 22463681, 40568913, 73266801, 132315810, 238948339, 431506179, 779231793, 1407175435
OFFSET
1,1
COMMENTS
Column 4 of A212402
LINKS
FORMULA
Empirical: a(n) = a(n-1) +a(n-2) +a(n-4) -a(n-6) +3*a(n-7) +8*a(n-8) -8*a(n-10) -8*a(n-11) -10*a(n-12) -5*a(n-13) +8*a(n-14) -2*a(n-15) -28*a(n-16) -15*a(n-17) +25*a(n-18) +24*a(n-19) +28*a(n-20) +24*a(n-21) -19*a(n-22) -18*a(n-23) +51*a(n-24) +40*a(n-25) -55*a(n-26) -16*a(n-27) -55*a(n-28) -45*a(n-29) +51*a(n-30) +36*a(n-31) -61*a(n-32) -45*a(n-33) +70*a(n-34) -16*a(n-35) +67*a(n-36) +40*a(n-37) -70*a(n-38) -19*a(n-39) +56*a(n-40) +24*a(n-41) -58*a(n-42) +24*a(n-43) -56*a(n-44) -15*a(n-45) +56*a(n-46) -2*a(n-47) -28*a(n-48) -5*a(n-49) +28*a(n-50) -8*a(n-51) +28*a(n-52) -28*a(n-54) +3*a(n-55) +8*a(n-56) -8*a(n-58) -8*a(n-60) +a(n-61) +8*a(n-62) -a(n-64) +a(n-66) +a(n-68) -a(n-70)
EXAMPLE
Some solutions for n=3
..0....0....1....0....0....0....1....0....0....0....1....1....0....1....1....0
..1....0....0....0....0....0....0....0....0....1....0....0....0....1....0....0
..1....0....1....0....1....1....0....0....0....1....1....1....0....0....0....0
..0....1....0....1....0....0....0....0....0....0....0....0....0....1....0....0
..0....0....0....0....0....1....1....1....0....1....1....1....0....0....0....0
..0....0....1....0....1....0....1....0....1....0....0....0....0....0....1....1
..0....1....1....1....1....0....0....0....1....1....0....1....0....1....0....0
..0....0....0....0....0....0....0....1....1....0....1....0....0....0....1....0
..1....1....0....0....0....1....1....0....0....0....1....0....0....1....1....1
..0....0....1....0....0....1....1....0....1....1....0....1....0....1....1....1
CROSSREFS
Sequence in context: A142534 A142695 A142772 * A157952 A306931 A142427
KEYWORD
nonn
AUTHOR
R. H. Hardin May 14 2012
STATUS
approved