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 A067866 #18 Jun 17 2017 03:04:36 %S A067866 736,1736,2736,3736,4736,5736,6736,7736,8736,9736,10736,11736,12736, %T A067866 13736,14736,15736,16736,17736,18736,19736,20736,21736,22736,23736, %U A067866 24736,25736,26736,27736,28736,29736,30736,31736,32736,33736,34736 %N A067866 Numbers n such that n and 2^n end with the same three digits. %H A067866 Tanya Khovanova, <a href="http://www.tanyakhovanova.com/RecursiveSequences/RecursiveSequences.html">Recursive Sequences</a> %H A067866 <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (2,-1). %F A067866 a(n) = 736 + 1000(n-1). %F A067866 a(n) = 2*a(n-1)-a(n-2). G.f.: 8*x*(92+33*x)/(1-x)^2. [_Colin Barker_, Dec 01 2012] %o A067866 (PARI) isok(n) = (2^n - n) % 1000 == 0; \\ _Michel Marcus_, Nov 23 2013 %Y A067866 Cf. A064541. %Y A067866 Subsequence of A067844 and A067845. %K A067866 easy,nonn,base %O A067866 1,1 %A A067866 _Benoit Cloitre_, Mar 07 2002