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A248441
Number of length n+5 0..1 arrays with no three disjoint pairs in any consecutive six terms having the same sum.
2
42, 62, 92, 136, 200, 292, 422, 612, 900, 1328, 1952, 2856, 4170, 6094, 8926, 13100, 19226, 28172, 41228, 60344, 88390, 129546, 189892, 278260, 407570, 596900, 874350, 1281060, 1877110, 2750284, 4029108, 5902172, 8646250, 12667042, 18558468
OFFSET
1,1
COMMENTS
Column 1 of A248448.
LINKS
FORMULA
Empirical: a(n) = a(n-3) + a(n-4) + a(n-5) + 3*a(n-6) + 2*a(n-7) + a(n-8) - 2*a(n-9) - 3*a(n-10) - 2*a(n-11) - a(n-12) - a(n-13) + a(n-15) + a(n-16).
Empirical g.f.: 2*x*(21 + 31*x + 46*x^2 + 47*x^3 + 48*x^4 + 48*x^5 + 3*x^6 - 43*x^7 - 85*x^8 - 78*x^9 - 44*x^10 - 18*x^11 - 3*x^12 + 19*x^13 + 27*x^14 + 16*x^15) / (1 - x^3 - x^4 - x^5 - 3*x^6 - 2*x^7 - x^8 + 2*x^9 + 3*x^10 + 2*x^11 + x^12 + x^13 - x^15 - x^16). - Colin Barker, Mar 19 2018
EXAMPLE
Some solutions for n=6:
..0....1....1....1....1....0....1....0....0....0....0....1....0....0....1....1
..0....0....0....1....0....1....0....1....1....1....0....1....1....1....1....0
..0....1....1....1....0....0....1....0....0....1....1....0....1....1....1....0
..0....0....0....0....1....0....1....0....0....0....0....1....1....0....1....0
..0....1....0....1....0....0....0....0....0....1....0....1....1....0....0....0
..1....1....0....1....0....0....1....0....1....1....0....1....0....0....1....1
..0....1....1....0....0....1....1....1....0....0....0....1....1....0....1....1
..0....1....0....1....1....0....1....1....1....1....0....0....0....0....1....0
..0....0....0....1....0....0....0....0....0....1....1....0....1....1....1....0
..1....0....1....1....0....0....1....0....0....0....1....1....1....0....1....0
..0....1....0....0....1....1....0....0....0....1....0....1....1....1....0....0
CROSSREFS
Cf. A248448.
Sequence in context: A300680 A053323 A363730 * A119650 A193343 A118074
KEYWORD
nonn
AUTHOR
R. H. Hardin, Oct 06 2014
STATUS
approved