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%I #13 Nov 03 2012 14:23:14
%S 9,10,12,14,16,17,18,20,22,23,24,25,27,31,37,39,41,43,49,53,54,62,67,
%T 71,74,77,78,79,81,82,84,85,90,91,93,94,108,109,111,112,117,118,120,
%U 122,124,125,130,131,133,134,148,149,151,152,157,158,160,161,162,164,168
%N Numbers with a distinct frequency for each ternary digit.
%C The smallest number in the sequence that actually contains all 3 ternary digits is 248 = 100012_3. [Corrected by _M. F. Hasler_, Nov 02 2012]
%C The number 28 is in A031948 but not in this sequence A167819. This sequence is infinite, e.g. all powers 3^k, k>1 are member. Digit frequencies are [2,1,0] for the first 12 terms (with 3 digits in base 3, from 100[3] to 221[3]), then [3,1,0] for the next 16 terms with 4 digits in base 3 (from 1000[3] to 2221[3]), then [4,1,0] and [3,2,0] (5 digits in base 3, from 10000[3] to 22221[3]), followed by [5,1,0] or [4,2,0] or [3,2,1] (6 digits in base-3, from 10000[3] to 22221[3]), etc. - _M. F. Hasler_, Nov 02 2012
%e 9 = 100_3 is in the sequence, as it has 2 0's, 1 1, and 0 2's.
%e 1 is not in the sequence, as it has the same number (0) of 0's and 2's.
%t Select[Range[168],Length[Union[DigitCount[ #,3]]]==3&] [From _Zak Seidov_, Nov 13 2009]
%o (PARI) /* In PARI versions < 2.6, define: */ digits(n,b=10)=local(r);r=[];while(n>0,r=concat([n%b],r);n\=b);r
%o is_A167819(n)=local(d=digits(n,3),v=vector(3));for(k=1,#d,v[d[k]+1]++);#Set(v)==3
%o for(n=1,250,if(is_A167819(n),print1(n",")))
%Y Cf. A121977, A044951.
%K base,nonn,fini
%O 1,1
%A _Franklin T. Adams-Watters_, Nov 13 2009
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