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 A130261 #10 Sep 08 2022 08:45:30
%S A130261 0,1,2,4,6,8,10,12,15,18,21,24,27,30,33,36,39,42,45,48,51,55,59,63,67,
%T A130261 71,75,79,83,87,91,95,99,103,107,111,115,119,123,127,131,135,139,143,
%U A130261 147,151,155,159,163,167,171,175,179,183,187,192,197,202,207,212,217
%N A130261 Partial sums of the 'lower' even Fibonacci Inverse A130259.
%H A130261 G. C. Greubel, <a href="/A130261/b130261.txt">Table of n, a(n) for n = 0..5000</a>
%F A130261 a(n) = (n+1)*A130259(n) - A001519(A130259(n)+1) + 1.
%F A130261 a(n) = (n+1)*A130259(n) - Fib(2*A130259(n)+1) + 1.
%F A130261 G.f.: g(x) = 1/(1-x)^2*Sum_{k>=1} x^Fib(2*k).
%t A130261 Table[Sum[Floor[1/2*Log[GoldenRatio, (Sqrt[5]*k + 1)]], {k, 0, n}], {n, 0, 50}] (* _G. C. Greubel_, Sep 12 2018 *)
%o A130261 (PARI) for(n=0,50, print1(sum(k=0,n, floor(log((sqrt(5)*k+1))/(2*log((1 +sqrt(5))/2)))), ", ")) \\ _G. C. Greubel_, Sep 12 2018
%o A130261 (Magma) [(&+[Floor(Log((Sqrt(5)*k+1))/(2*Log((1+Sqrt(5))/2))): k in [0..n]]): n in [0..50]]; // _G. C. Greubel_, Sep 12 2018
%Y A130261 Cf. A000045, A001519, A001906, A130233, A130235, A130236, A130255, A130257, A104162. Lucas inverse: A130241 - A130248.
%K A130261 nonn
%O A130261 0,3
%A A130261 _Hieronymus Fischer_, May 25 2007