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 A183613 #23 Feb 09 2018 09:09:47 %S A183613 7,87,387,5387,95387,195387,4195387,64195387,464195387,2464195387, %T A183613 62464195387,262464195387,7262464195387,27262464195387, %U A183613 627262464195387,5627262464195387,75627262464195387,575627262464195387,4575627262464195387,4575627262464195387 %N A183613 a(n) = 3^^(n+1) modulo 10^n. %C A183613 Backward concatenation of A133613. %C A183613 For all m>n, 3^^m == 3^^(n+1) (mod 10^n). Hence, each term represents the tailing decimal digits of 3^^m for all sufficiently large m. %D A183613 M. Ripà, La strana coda della serie n^n^...^n, Trento, UNI Service, Nov 2011, p. 11-12, 69-78. ISBN 978-88-6178-789-6. %H A183613 J. Jimenez Urroz and J. Luis A. Yebra, <a href="http://www.cs.uwaterloo.ca/journals/JIS/VOL12/Yebra/yebra4.html">On the equation a^x == x (mod b^n)</a>, J. Int. Seq. 12 (2009) #09.8.8. %F A183613 For n>1, a(n) = 3^a(n-1) mod 10^n. %K A183613 nonn %O A183613 1,1 %A A183613 _Max Alekseyev_, Sep 08 2011