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A292543
Number of 5-cycles in the n-Sierpinski tetrahedron graph.
3
0, 96, 384, 1536, 6144, 24576, 98304, 393216, 1572864, 6291456, 25165824, 100663296, 402653184, 1610612736, 6442450944, 25769803776, 103079215104, 412316860416, 1649267441664, 6597069766656, 26388279066624, 105553116266496, 422212465065984, 1688849860263936
OFFSET
1,2
LINKS
Eric Weisstein's World of Mathematics, Graph Cycle
Eric Weisstein's World of Mathematics, Sierpinski Tetrahedron Graph
FORMULA
a(n) = 6*4^n = A002023(n) for n > 1.
a(n) = 4*a(n-1) for n > 2.
G.f.: 96*x^/(1 - 4*x).
MATHEMATICA
Table[If[n == 1, 0, 6 4^n], {n, 20}]
Join[{0}, LinearRecurrence[{4}, {96}, 20]]
CoefficientList[Series[96 x/(1 - 4 x), {x, 0, 20}], x]
CROSSREFS
Cf. A002023 (6*4^n).
Cf. A292540 (3-cycles), A292542 (4-cycles), A292545 (6-cycles).
Sequence in context: A248457 A051483 A277107 * A051465 A179825 A304515
KEYWORD
nonn,easy
AUTHOR
Eric W. Weisstein, Sep 18 2017
STATUS
approved