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 A037897 #21 Aug 12 2017 06:02:22 %S A037897 0,0,1,0,1,2,1,0,1,1,2,1,0,1,2,1,1,2,2,2,2,1,1,2,1,0,1,1,2,1,1,2,2,2, %T A037897 2,1,1,2,1,0,1,2,1,1,2,2,2,2,1,1,2,1,1,2,2,2,2,2,2,2,2,2,2,2,2,2,1,1, %U A037897 2,1,1,2,2,2,2,1,1,2,1,0,1,1,2,1,1,2,2,2,2,1,1,2,1,1,2,2,2,2,2,2,2,2,2,2,2 %N A037897 (Greatest base 3 digit of n)-(least base 3 digit of n). %H A037897 Antti Karttunen, <a href="/A037897/b037897.txt">Table of n, a(n) for n = 1..19683</a> %F A037897 a(n) = A190592(n) - A290825(n). - _Antti Karttunen_, Aug 12 2017 %p A037897 A037897 := proc(n) %p A037897 local dgs ; %p A037897 dgs := convert(n,base,3); %p A037897 max(op(dgs))-min(op(dgs)) ; %p A037897 end proc: # _R. J. Mathar_, Oct 19 2015 %o A037897 (PARI) A037897(n) = (vecmax(digits(n,3)) - vecmin(digits(n,3))); \\ _Antti Karttunen_, Aug 11 2017 %Y A037897 Cf. A007089, A043530, A190592, A290825. %K A037897 nonn,base %O A037897 1,6 %A A037897 _Clark Kimberling_ %E A037897 Offset corrected by _R. J. Mathar_, Oct 19 2015 %E A037897 More terms from _Antti Karttunen_, Aug 11 2017