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A287471
Number of connected dominating sets in the n-crown graph.
2
13, 115, 666, 3234, 14379, 60981, 251968, 1026124, 4145241, 16670823, 66879606, 267944070, 1072693399, 4292739241, 17175150780, 68709515472, 274856935653, 1099467587835, 4397954236690, 17591993106730, 70368341524803, 281474137850205, 1125898162012536
OFFSET
3,1
COMMENTS
A connected dominating set in the crown graph requires a minimum two vertices on each side of the graph which cannot be two pairs of opposing vertices. - Andrew Howroyd, Jun 03 2017
LINKS
Eric Weisstein's World of Mathematics, Connected Dominating Set
Eric Weisstein's World of Mathematics, Crown Graph
FORMULA
a(n) = (2^n-n-1)^2 - n*(n-1)/2. - Andrew Howroyd, Jun 03 2017
From Colin Barker, Jun 03 2017: (Start)
G.f.: x^3*(13 - 28*x + 12*x^2) / ((1 - x)^3*(1 - 2*x)^2*(1 - 4*x)).
a(n) = 11*a(n-1) - 47*a(n-2) + 101*a(n-3) - 116*a(n-4) + 68*a(n-5) - 16*a(n-6) for n>8.
(End)
PROG
(PARI) Vec(x^3*(13 - 28*x + 12*x^2) / ((1 - x)^3*(1 - 2*x)^2*(1 - 4*x)) + O(x^30)) \\ Colin Barker, Jun 03 2017
CROSSREFS
Sequence in context: A323037 A320617 A156969 * A016765 A362514 A115188
KEYWORD
nonn,easy,changed
AUTHOR
Eric W. Weisstein, May 25 2017
EXTENSIONS
Term a(13) and beyond from Andrew Howroyd, Jun 03 2017
STATUS
approved