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 A129286 #14 Nov 29 2019 20:52:52 %S A129286 5,6,11,12,28,60,152,388,780,2036,4076,8156,16316,32636,66232,169612, %T A129286 339228,1244808,4856004,14568120,56648484,190791072,866874960, %U A129286 4084880112,16342519392,73816544592,305811402048,1732931293824,10145637246528,52715820454848 %N A129286 a(n) = A129152(n) / 5^5, where A129152 is the trajectory of 5^6 under A003415, the arithmetic derivative. %F A129286 a(n+1) = A129283(a(n)), a(0) = 5. %F A129286 a(n) = A090635(n+3) / 4, i.e., the trajectory of 20 under A003415, divided by the common factor 4. - _M. F. Hasler_, Nov 27 2019 %o A129286 (Haskell) %o A129286 a129286 n = a129286_list !! n %o A129286 a129286_list = iterate a129283 5 -- _Reinhard Zumkeller_, Nov 01 2013 %Y A129286 Cf. A129284, A129285, A051674. %K A129286 nonn %O A129286 0,1 %A A129286 _Reinhard Zumkeller_, Apr 07 2007