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 A025665 #7 Jul 06 2025 13:50:56 %S A025665 0,0,1,0,1,0,2,1,0,2,1,0,3,2,1,0,3,2,1,0,4,3,2,1,0,4,3,2,1,5,0,4,3,2, %T A025665 1,5,0,4,3,2,6,1,5,0,4,3,2,6,1,5,0,4,3,7,2,6,1,5,0,4,3,7,2,6,1,5,0,4, %U A025665 8,3,7,2,6,1,5,0,4,8,3,7,2,6,1,5,9,0,4,8,3,7,2,6,1,5,9,0,4,8,3,7,2,6,10,1,5,9,0 %N A025665 Exponent of 7 (value of j) in n-th number of form 3^i*7^j. %Y A025665 Cf. A003594. %K A025665 nonn %O A025665 1,7 %A A025665 _David W. Wilson_