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A297028
Number of edge covers in the 2n-crossed prism graph.
3
43, 1699, 69868, 2877415, 118509133, 4880925010, 201026119435, 8279475869551, 340999074533188, 14044411828143979, 578434131730636609, 23823428766200974018, 981193410008781864847, 40411500682493314776379, 1664390904741748307208988, 68549720673628283984136223
OFFSET
1,1
COMMENTS
Sequence extrapolated to a(1) using recurrence. - Andrew Howroyd, Dec 27 2017
LINKS
Eric Weisstein's World of Mathematics, Crossed Prism Graph
Eric Weisstein's World of Mathematics, Edge Cover
FORMULA
From Andrew Howroyd, Dec 27 2017: (Start)
a(n) = 43*a(n-1) - 75*a(n-2) + 12*a(n-3).
G.f.: x*(43 - 150*x + 36*x^2)/(1 - 43*x + 75*x^2 - 12*x^3).
(End)
MATHEMATICA
Table[RootSum[-12 + 75 # - 43 #^2 + #^3 &, #^n &], {n, 20}]
RootSum[-12 + 75 # - 43 #^2 + #^3 &, #^Range[20] &]
LinearRecurrence[{43, -75, 12}, {43, 1699, 69868}, 20]
CoefficientList[Series[(-43 + 150 x - 36 x^2)/(-1 + 43 x - 75 x^2 + 12 x^3), {x, 0, 20}], x]
PROG
(PARI) Vec((43 - 150*x + 36*x^2)/(1 - 43*x + 75*x^2 - 12*x^3) + O(x^20)) \\ Andrew Howroyd, Dec 27 2017
CROSSREFS
Sequence in context: A014938 A235646 A022220 * A198206 A162881 A163226
KEYWORD
nonn
AUTHOR
Eric W. Weisstein, Dec 24 2017
EXTENSIONS
a(1) and terms a(5) and beyond from Andrew Howroyd, Dec 27 2017
STATUS
approved