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A292055
Wiener index of the n-Mycielski graph.
0
0, 1, 15, 90, 435, 1926, 8175, 33930, 139035, 565326, 2287335, 9224370, 37116435, 149110326, 598350495, 2399080410, 9613258635, 38503648926, 154166045655, 617117746050, 2469830101635, 9883394613126, 39545794780815, 158219815525290, 632989146141435
OFFSET
1,3
LINKS
Eric Weisstein's World of Mathematics, Mycielski Graph
Eric Weisstein's World of Mathematics, Wiener Index
FORMULA
a(n) = (216 - 27*2^(n + 3) - 56*3^n + 81*4^n)/144 for n > 1.
a(n) = 10*a(n-1) - 35*a(n-2) + 50*a(n-3) - 24*a(n-4).
G.f.: x^2*(1 + 5*x - 25*x^2 + 10*x^3)/(1 - 10*x + 35*x^2 - 50*x^3 + 24*x^4).
MATHEMATICA
Table[If[n == 1, 0, (216 - 27 2^(n + 3) - 56 3^n + 81 4^n)/144], {n,
30}]
Join[{0}, LinearRecurrence[{10, -35, 50, -24}, {1, 15, 90, 435}, 20]]
CoefficientList[Series[x (1 + 5 x - 25 x^2 + 10 x^3)/(1 - 10 x + 35 x^2 - 50 x^3 + 24 x^4), {x, 0, 20}], x]
CROSSREFS
Sequence in context: A328994 A001297 A005716 * A263628 A263629 A320524
KEYWORD
nonn,easy
AUTHOR
Eric W. Weisstein, Sep 08 2017
STATUS
approved