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%I #34 Jul 31 2021 20:09:10
%S 1,17,51,391,1649,9945,47923,264911,1344513,7192513,37241747,
%T 196756215,1026622129,5398099913,28248776019,148265250559,
%U 776759693441,4074028646385,21352972081267,111964431151079,586929387683697,3077254104935737,16132307800494323
%N G.f.: (1 + 15*x) / (1 - 2*x - 17*x^2).
%H Colin Barker, <a href="/A330390/b330390.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 (2,17).
%F a(n) = 2*a(n-1) + 17*a(n-2) for n>1.
%F a(n)/a(n-1) ~ 1 + 3*sqrt(2).
%F a(n) = ((1 - 3*sqrt(2))^n*(-16+3*sqrt(2)) + (1+3*sqrt(2))^n*(16 + 3*sqrt(2))) / (6*sqrt(2)). - _Colin Barker_, Dec 14 2019
%t CoefficientList[Series[(1+15x)/(1-2x-17x^2),{x,0,30}],x] (* or *) LinearRecurrence[{2,17},{1,17},30] (* _Harvey P. Dale_, Jul 31 2021 *)
%o (PARI) Vec((1 + 15*x) / (1 - 2*x - 17*x^2) + O(x^25)) \\ _Colin Barker_, Jan 25 2020
%Y Cf. A164544, A328606.
%K nonn,easy
%O 0,2
%A _Kyle MacLean Smith_, Dec 13 2019
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