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 A235669 #11 Jan 27 2014 12:09:30 %S A235669 0,1,2,3,2,3,6,3,4,9,4,5,4,3,4,7,4,5,18,7,8,5,4,5,8,5,6,27,10,11,6,5, %T A235669 6,9,6,7,10,5,6,5,4,5,8,5,6,19,8,9,6,5,6,9,6,7,54,19,20,9,8,9,12,9,10, %U A235669 11,6,7,6,5,6,9,6,7,20,9,10,7,6,7,10,7,8,81,28,29,12 %N A235669 Sum of parts of the form 10...0 and 20...0 with nonnegative number of zeros in ternary representation of n as the corresponding numbers 3^n and 2*3^n. %C A235669 The number of appearances of k is the number of compositions of k into numbers of the form 3^n and 2*3^n, A235684(k). %H A235669 Alois P. Heinz, <a href="/A235669/b235669.txt">Table of n, a(n) for n = 0..10000</a> %t A235669 bitPatt[n_,b_]:=Split[IntegerDigits[n,b ],#2==0&]; Map[Plus@@Map[FromDigits[#,3]&,bitPatt[#,3]]&,Range[0,50]] (* _Peter J. C. Moses_, Jan 13 2014 *) %Y A235669 Cf. A124771, A162439, A233249, A233312, A233416, A233420, A233564, A233569, A233655. %K A235669 nonn,base,look %O A235669 0,3 %A A235669 _Vladimir Shevelev_, Jan 13 2014