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 A060582 #5 Mar 30 2012 18:51:33 %S A060582 0,2,1,1,0,2,2,1,0,2,1,0,0,2,1,1,0,2,1,0,2,2,1,0,0,2,1,1,0,2,2,1,0,0, %T A060582 2,1,0,2,1,1,0,2,2,1,0,2,1,0,0,2,1,1,0,2,2,1,0,0,2,1,1,0,2,1,0,2,2,1, %U A060582 0,0,2,1,0,2,1,1,0,2,2,1,0,2,1,0,0,2,1,1,0,2,1,0,2,2,1,0,0,2,1,0,2,1,1,0,2 %N A060582 If the final digit of n in base 3 is the same as a([n/3]) then this digit, otherwise a(n)= mod 3-sum of these two digits, with a(0)=0. %H A060582 <a href="/index/Fi#final">Index entries for sequences related to final digits of numbers</a> %F A060582 a(n) =(-a([n/3])-n) mod 3 =A060583(n) mod 3. %e A060582 a(4)=0 since a([4/3])=a(1)=2, (4 mod 3)=1 and 3-2-1=0. a(5)=2 since a([5/3])=a(1)=2 and (5 mod 3)=2. %Y A060582 Cf. A060588. %K A060582 base,nonn %O A060582 0,2 %A A060582 _Henry Bottomley_, Apr 04 2001