This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A171495 #6 Jun 30 2023 15:10:24
%S A171495 6,22,70,214,646,1942,5830,17494,52486,157462,472390,1417174,4251526,
%T A171495 12754582,38263750,114791254,344373766,1033121302,3099363910,
%U A171495 9298091734,27894275206,83682825622,251048476870,753145430614,2259436291846
%N A171495 a(n) = 3*a(n-1)+4 for n > 0; a(0) = 6.
%C A171495 Binomial transform of A171494; second binomial transform of A010726.
%C A171495 Inverse binomial transform of A171496.
%H A171495 <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (4, -3).
%F A171495 a(n) = 2*(4*3^n-1).
%F A171495 G.f.: 2*(3-x)/((1-x)*(1-3*x)).
%t A171495 NestList[3#+4&,6,30] (* _Harvey P. Dale_, Aug 25 2019 *)
%o A171495 (PARI) {m=25; v=concat([6], vector(m-1)); for(n=2, m, v[n]=3*v[n-1]+4); v}
%Y A171495 Equals 2*A171498.
%Y A171495 Cf. A010726 (repeat 6, 10), A171494, A171496.
%K A171495 nonn
%O A171495 0,1
%A A171495 _Klaus Brockhaus_, Dec 10 2009