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 A290568 #16 Aug 07 2017 09:12:07 %S A290568 0,2,12,87,212,212,9587,56462,212712,603337,4509587,4509587,4509587, %T A290568 4509587,2445915837,20756462712,142826775212,600590447087, %U A290568 2889408806462,18148197868962,94442143181462,94442143181462,1524953617790837,6293325199822087,6293325199822087,125502614750603337 %N A290568 The successive approximations up to 5^n for 5-adic integer 3^(1/3). %C A290568 x = ...301322, %C A290568 x^2 = ...114234, %C A290568 x^3 = ...000003 = 3. %H A290568 Seiichi Manyama, <a href="/A290568/b290568.txt">Table of n, a(n) for n = 0..1431</a> %H A290568 Wikipedia, <a href="https://en.wikipedia.org/wiki/Hensel%27s_lemma">Hensel's Lemma</a>. %F A290568 a(0) = 0 and a(1) = 2, a(n) = a(n-1) + 2 * (a(n-1)^3 - 3) mod 5^n for n > 1. %e A290568 a(1) = ( 2)_5 = 2, %e A290568 a(2) = ( 22)_5 = 12, %e A290568 a(3) = ( 322)_5 = 87, %e A290568 a(4) = (1322)_5 = 212. %o A290568 (PARI) a(n)=truncate((3+O(5^n))^(1/3)); \\ _Joerg Arndt_, Aug 06 2017 %Y A290568 Cf. A290563, A290567. %K A290568 nonn %O A290568 0,2 %A A290568 _Seiichi Manyama_, Aug 06 2017