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A007386
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Number of strict 7th-order maximal independent sets in path graph.
(Formerly M2199)
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0
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0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 3, 0, 6, 0, 10, 0, 15, 1, 21, 4, 28, 10, 36, 20, 45, 35, 56, 56, 71, 84, 93, 120, 126, 165, 175, 221, 246, 292, 346, 385, 483, 511, 666, 686, 906, 932, 1218, 1278, 1624, 1761, 2157, 2427, 2866, 3333, 3822, 4551
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OFFSET
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1,11
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REFERENCES
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N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
R. Yanco and A. Bagchi, "K-th order maximal independent sets in path and cycle graphs", J. Graph Theory, submitted, 1994, apparently unpublished.
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LINKS
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Table of n, a(n) for n=1..56.
R. Yanco, Letter and Email to N. J. A. Sloane, 1994
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FORMULA
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Apparently, g.f. = -x^9/((x^9+x^2-1)*(x-1)^2*(1+x)^2) with recurrence a(n)= 3*a(n-2) - 3*a(n-4) + a(n-6) + a(n-9) - 2*a(n-11) + a(n-13). - R. J. Mathar, Oct 30 2009
a(n) = A007381(n) - b(n) where b(2*n+1) = 1 and b(2*n) = n+1. - Sean A. Irvine, Jan 02 2018
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CROSSREFS
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Cf. A007381.
Sequence in context: A290705 A115456 A328788 * A007385 A307644 A081978
Adjacent sequences: A007383 A007384 A007385 * A007387 A007388 A007389
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KEYWORD
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nonn
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AUTHOR
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N. J. A. Sloane, Mira Bernstein
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EXTENSIONS
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More terms from Sean A. Irvine, Jan 02 2018
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STATUS
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approved
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