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%I #10 Jun 09 2016 12:03:14
%S 0,7,35,217,1295,7777,46655,279937,1679615,10077697,60466175,
%T 362797057,2176782335,13060694017,78364164095,470184984577,
%U 2821109907455,16926659444737,101559956668415,609359740010497,3656158440062975,21936950640377857,131621703842267135
%N a(n) = 6^n-(-1)^n.
%H Colin Barker, <a href="/A274073/b274073.txt">Table of n, a(n) for n = 0..1000</a>
%H <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (5,6).
%F O.g.f.: 7*x/((1+x)*(1-6*x)).
%F E.g.f.: exp(6*x) - exp(-x).
%F a(n) = 5*a(n-1) + 6*a(n-2) for n>1.
%F a(n) = 7*A015540(n).
%o (PARI) concat(0, Vec(7*x/((1+x)*(1-6*x)) + O(x^30)))
%Y Cf. A015540.
%Y Sequences of the type k^n-(-1)^n: A062157 (k=0), A010673 (k=1), A062510 (k=2), A105723 (k=3), A247281 (k=4), A274072 (k=5), this sequence (k=6).
%K nonn,easy
%O 0,2
%A _Colin Barker_, Jun 09 2016
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