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A291938 a(n) = 2^(n - 1) (n - mod(n, 2)). 0
0, 4, 8, 32, 64, 192, 384, 1024, 2048, 5120, 10240, 24576, 49152, 114688, 229376, 524288, 1048576, 2359296, 4718592, 10485760, 20971520, 46137344, 92274688, 201326592, 402653184, 872415232, 1744830464, 3758096384, 7516192768, 16106127360 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Agrees with independence number of the n-cube connected cycle graph for at least 3 <= n <= 8.

LINKS

Table of n, a(n) for n=1..30.

Eric Weisstein's World of Mathematics, Cube-Connected Cycle Graph

Eric Weisstein's World of Mathematics, Independence Number

Index entries for linear recurrences with constant coefficients, signature (2, 4, -8).

FORMULA

a(n) = 2^(n - 1) (n - mod(n, 2)).

a(n) = 2*a(n-1) + 4*a(n-2) - 8*a(n-3).

G.f.: (4 x^2)/((1 - 2 x)^2 (1 + 2 x)).

MATHEMATICA

Table[2^(n - 1) (n - Mod[n, 2]), {n, 20}]

LinearRecurrence[{2, 4, -8}, {0, 4, 8}, 20]

CoefficientList[Series[(4 x)/((1 - 2 x)^2 (1 + 2 x)), {x, 0, 20}], x]

CROSSREFS

Sequence in context: A050442 A229953 A331408 * A094015 A094867 A149093

Adjacent sequences:  A291935 A291936 A291937 * A291939 A291940 A291941

KEYWORD

nonn,

AUTHOR

Eric W. Weisstein, Sep 06 2017

STATUS

approved

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Last modified June 6 18:59 EDT 2020. Contains 334832 sequences. (Running on oeis4.)