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 A054291 #18 Jul 31 2019 19:03:35 %S A054291 23,31,49,58,67,105,112,120,134,156,167,169,173,178,205,215,242,264, %T A054291 277,282,285,295,298,329,331,338,353,368,388,393,395,408,416,450,453, %U A054291 469,487,507,516,524,527,539,555,570,580,587,627,634,651,659,672,678,687 %N A054291 Positions of 5's in the decimal expansion of (1+sqrt(5))/2. %H A054291 G. C. Greubel, <a href="/A054291/b054291.txt">Table of n, a(n) for n = 1..10000</a> %t A054291 Flatten[Position[RealDigits[GoldenRatio, 10, 500][[1]], 5]] (* _G. C. Greubel_, Jul 31 2019 *) %Y A054291 Cf. A001622. %K A054291 nonn,base %O A054291 1,1 %A A054291 _Simon Plouffe_, Feb 20 2000