cp's OEIS Frontend

A095204 a(n) is the smallest number greater than a(n-1) such that in a(0) through a(n) no digit occurs more than once more than any other digit.

%I A095204 #23 Sep 04 2015 04:49:59
%S A095204 0,1,2,3,4,5,6,7,8,9,10,23,45,67,89,90,123,456,478,501,623,789,790,
%T A095204 812,3456,3457,6012,6089,7123,8459,8460,9123,9157,20345,20678,31456,
%U A095204 31789,40256,40789,51236,51789,60234,60789,71234,71589,80234,80569,91234,91567
%N A095204 a(n) is the smallest number greater than a(n-1) such that in a(0) through a(n) no digit occurs more than once more than any other digit.
%C A095204 Question: Formula for a(n)?
%C A095204 Note that, almost always, if the number of digits in a(0) through a(n) is a multiple of 10, a(n+1) = a(n) + 1. (The only exceptions would be if a(n) + 1 had some digit two more times than some other digit.) - _Franklin T. Adams-Watters_, Jan 11 2006
%H A095204 Robert Israel, <a href="/A095204/b095204.txt">Table of n, a(n) for n = 0..91</a>
%e A095204 After 10 the next term is 23 and not 11. Any number containing 0 or 1 would occur only after all the digits from 2 to 9 have occurred once.
%p A095204 counts:= Array(0..9):
%p A095204 cp:= Array(0..9):
%p A095204 counts[0]:= 1:
%p A095204 A[0]:= 0:
%p A095204 for n from 1 to 70 do
%p A095204   for x from A[n-1]+1 do
%p A095204      L:= convert(x,base,10);
%p A095204      ArrayTools:-Copy(counts,cp);
%p A095204      for t in L do cp[t]:= cp[t]+1 od:
%p A095204      if max(cp) - min(cp) <= 1 then
%p A095204         A[n]:= x;
%p A095204         ArrayTools:-Copy(cp,counts);
%p A095204         break
%p A095204      fi
%p A095204   od
%p A095204 od:
%p A095204 seq(A[i],i=0..70); # _Robert Israel_, Sep 03 2015
%Y A095204 Cf. A120125 (non-monotonic version).
%K A095204 base,nonn
%O A095204 0,3
%A A095204 _Amarnath Murthy_, Jun 06 2004
%E A095204 Edited, corrected and extended by _Franklin T. Adams-Watters_, Jan 11 2006