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 A060372 #11 Mar 06 2015 23:08:00 %S A060372 0,1,3,3,4,9,9,10,9,9,10,12,12,13,27,27,28,27,27,28,30,30,31,27,27,28, %T A060372 27,27,28,30,30,31,36,36,37,36,36,37,39,39,40,81,81,82,81,81,82,84,84, %U A060372 85,81,81,82,81,81,82,84,84,85,90,90,91,90,90,91,93,93,94,81,81,82,81 %N A060372 p(n), positive part of n when n=p(n)-q(n) with p(n), q(n), p(n)+q(n) in A005836, integers written without 2 in base 3. %C A060372 The graphs of p(n), q(n) are fractals; the graph of p(n)+q(n) is Sierpiński-like. %H A060372 Reinhard Zumkeller, <a href="/A060372/b060372.txt">Table of n, a(n) for n = 0..10000</a> %e A060372 Example: 14=27-13=3^3 -(3^0+3^1+3^2), 16=28-12=3^3+3^0 -(3^1+3^2), 20=30-10=3^3+3^1 -(3^0+3^2); 27+13=28+12=30+10=40; 10,12,13, 27, 28, 30 are written without 2 in base 3. %o A060372 (Haskell) %o A060372 a060372 n = (a060374 n + n) `div` 2 -- _Reinhard Zumkeller_, Jun 09 2012 %Y A060372 Cf. A005836, A060373, A060374. %K A060372 easy,nice,nonn %O A060372 0,3 %A A060372 Claude Lenormand (claude.lenormand(AT)free.fr), Apr 02 2001