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5th-order maximal independent sets in cycle graph.
(Formerly M0425)
3

%I M0425 #35 Feb 02 2021 20:42:53

%S 0,2,3,2,5,2,7,2,9,2,11,2,13,9,15,18,17,29,19,42,28,57,46,74,75,93,

%T 117,121,174,167,248,242,341,359,462,533,629,781,871,1122,1230,1584,

%U 1763,2213,2544,3084,3666,4314,5250,6077,7463,8621,10547

%N 5th-order maximal independent sets in cycle graph.

%D N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

%D R. Yanco and A. Bagchi, K-th order maximal independent sets in path and cycle graphs, J. Graph Theory, submitted, 1994, apparently unpublished.

%H R. Yanco, <a href="/A007380/a007380.pdf">Letter and Email to N. J. A. Sloane, 1994</a>

%H R. Yanco and A. Bagchi, <a href="/A007380/a007380_1.pdf">K-th order maximal independent sets in path and cycle graphs</a>, Unpublished manuscript, 1994. (Annotated scanned copy)

%F Empirical g.f.: x^2*(5*x^10+3*x^8-2*x^5-2*x^3-3*x-2) / (x^7+x^2-1). - _Colin Barker_, Mar 29 2014

%F For n >= 13: a(n) = a(n-2) + a(n-7). - _Sean A. Irvine_, Jan 02 2018

%F a(n) = Sum_{j=0..floor((n-g)/(2*g))} (2*n/(n-2*(g-2)*j-(g-2))) * Hypergeometric2F1([-(n-2g*j-g)/2,-(2j+1)], [1], 1), g = 7, n >= g and n an odd integer. - _Richard Turk_, Oct 14 2019

%Y Cf. A001608, A007387, A007389.

%K nonn

%O 1,2

%A _N. J. A. Sloane_, _Mira Bernstein_

%E Typo in data (242 was inadvertently repeated) fixed by _Colin Barker_, Mar 29 2014

%E More terms from _Sean A. Irvine_, Jan 02 2018