%I #3 Mar 31 2012 13:22:18
%S 11,111,122,212,221,1111,1222,2122,2212,2221,11111,12221,21222,22122,
%T 22212,111111,122212,122221,133322,212221,221222,222122,223331,
%U 1111111,1222122,1222212,1222221,1333222,2122212,2122221,2212221,2221222
%N k th digit of a(n) is the number of different digits within 3 of k (not including k).
%K base,easy,nonn
%O 0,1
%A _Erich Friedman_