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 A025670 #7 Jul 06 2025 14:29:25 %S A025670 0,1,0,2,1,0,3,2,1,0,4,3,2,1,0,5,4,3,2,1,0,6,5,4,3,2,1,0,7,6,5,4,3,2, %T A025670 1,0,8,7,6,5,4,3,2,1,9,0,8,7,6,5,4,3,2,10,1,9,0,8,7,6,5,4,3,11,2,10,1, %U A025670 9,0,8,7,6,5,4,12,3,11,2,10,1,9,0,8,7,6,5,13,4,12,3,11,2,10,1,9,0,8,7,6,14,5 %N A025670 Exponent of 7 (value of i) in n-th number of form 7^i*9^j. %Y A025670 Cf. A025631. %K A025670 nonn %O A025670 1,4 %A A025670 _David W. Wilson_