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Integers whose decimal representation consists of three distinct digits, one appearing once, one appearing twice, and one appearing three times.
6

%I #36 Aug 03 2014 14:01:27

%S 100012,100013,100014,100015,100016,100017,100018,100019,100021,

%T 100022,100031,100033,100041,100044,100051,100055,100061,100066,

%U 100071,100077,100081,100088,100091,100099,100102,100103,100104,100105,100106,100107,100108,100109,100112

%N Integers whose decimal representation consists of three distinct digits, one appearing once, one appearing twice, and one appearing three times.

%C There are 38880 terms, including 41 squares (A182098) and 3640 primes (A182092). - _Zak Seidov_, Apr 12 2012

%C This is the subsequence of A218556 consisting of terms with indices n = 254, ..., 39133. The number of terms is 38880 = A218566(10,3), the starting index is 254 = 1 + A218566(10,1) + A218566(10,2) + 1. - _M. F. Hasler_, Nov 02 2012

%H Charles R Greathouse IV, <a href="/A182040/b182040.txt">Table of n, a(n) for n = 1..38880</a> (complete sequence)

%t t = Select[Range[100000, 999999], Sort[Transpose[Tally[IntegerDigits[#]]][[2]]] == {1, 2, 3} &]; Take[t, 32] (* _T. D. Noe_, Apr 11 2012 *)

%o (PARI) is(n)=n=vecsort(eval(Vec(Str(n))));vecsort(apply(k->sum(i=1, #n,n[i]==k),vecsort(n,,8)))==[1,2,3] \\ _Charles R Greathouse IV_, Apr 11 2012

%Y Cf. A071925, A181986 (digitally balanced numbers: ternary numbers which have the same number of 0's as 1's as 2's), A182051 (primes with a majority of one digit).

%K nonn,base,fini,full,easy

%O 1,1

%A _Jonathan Vos Post_, Apr 09 2012