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 A256297 #4 Mar 23 2015 07:14:22 %S A256297 1,2,3,4,5,6,0,15,16,17,18,19,20,14,22,23,24,25,26,27,21,29,30,31,32, %T A256297 33,34,28,36,37,38,39,40,41,35,43,44,45,46,47,48,42,1,2,3,4,5,6,0,106, %U A256297 107,108,109,110,111,105,113,114,115,116 %N A256297 Apply the transformation 0 -> 1 -> 2 -> 3 -> 4 -> 5 -> 6 -> 0 to the digits of n written in base 7, then convert back to base 10. %C A256297 Base 7 variant of A035327 (base 2) and A048379 (base 10). See A256293 - A256299 for bases 3 through 9, and A256307 for the variant where the result is not converted back to base 10. %e A256297 a(7) = 15 because 7 = 10[7] becomes 21[7] = 15. %e A256297 a(48) = 0 because 48 = 66[7] becomes 00[7] = 0. %o A256297 (PARI) A256297(n,b=7)=!n+apply(t->(t+1)%b,n=digits(n,b))*vector(#n,i,b^(#n-i))~ %K A256297 nonn,base,easy %O A256297 0,2 %A A256297 _M. F. Hasler_, Mar 22 2015