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URL: https://oeis.org/A291537

⇱ A291537 - OEIS

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A291537
a(n) = 8^n - 3*2^n + 5.
3
7, 57, 493, 4053, 32677, 261957, 2096773, 16776453, 134216197, 1073738757, 8589928453, 68719464453, 549755789317, 4398046461957, 35184371990533, 281474976514053, 2251799813292037, 18014398508695557, 144115188074283013, 1152921504603701253, 9223372036848484357
OFFSET
1,1
COMMENTS
Number of dominating sets in the n X n X n complete tripartite graph.
LINKS
Eric Weisstein's World of Mathematics, Complete Tripartite Graph
Eric Weisstein's World of Mathematics, Dominating Set
FORMULA
a(n) = 8^n - 3*2^n + 5.
a(n) = 11*a(n-1) - 26*a(n-2) + 16*a(n-3).
G.f.: x*(7 - 20*x + 48*x^2)/(1 - 11*x + 26*x^2 - 16*x^3).
E.g.f.: exp(8*x) - 3*exp(2*x) + 5*exp(x) - 3. - G. C. Greubel, Aug 26 2017
MATHEMATICA
Table[8^n - 3 2^n + 5, {n, 20}]
LinearRecurrence[{11, -26, 16}, {7, 57, 493}, 20]
CoefficientList[Series[(-7 + 20 x - 48 x^2)/(-1 + 11 x - 26 x^2 + 16 x^3), {x, 0, 20}], x]
PROG
(PARI) x='x+O('x^50); Vec(x*(7 - 20*x + 48*x^2)/(1 - 11*x + 26*x^2 - 16*x^3)) \\ G. C. Greubel, Aug 26 2017
CROSSREFS
Sequence in context: A349303 A268316 A390335 * A082413 A142990 A202250
KEYWORD
nonn,easy
AUTHOR
Eric W. Weisstein, Aug 25 2017
STATUS
approved