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Nonnegative integers where all occurring digits occur with equal frequency.
3

%I #22 Jan 09 2016 14:55:40

%S 0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18,19,20,21,22,23,24,25,

%T 26,27,28,29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,

%U 49,50,51,52,53,54,55,56,57,58,59,60,61,62,63,64,65,66,67

%N Nonnegative integers where all occurring digits occur with equal frequency.

%C The set of terms of this sequence is a superset of each of the sets of terms of A050278 and A082810.

%C Except for i = 1, A261315(i) gives the number of existing n such that A055642(a(n)) = i.

%H Felix Fröhlich, <a href="/A266279/b266279.txt">Table of n, a(n) for n = 1..10000</a>

%e 1122 is a term of the sequence, since all occurring digits occur twice.

%t Select[Range[0, 67], Length@ Union[DigitCount[#] /. 0 -> Nothing] == 1 &] (* _Michael De Vlieger_, Jan 06 2016 *)

%o (PARI) digitcount(n) = my(d=digits(n), v=vector(10)); for(x=0, 9, for(k=1, #d, if(d[k]==x, v[x+1]++))); v

%o is(n) = my(c=digitcount(n), k=0); for(i=1, #c, if(k==0 && c[i]!=0, k=c[i]); if(k!=0 && c[i]!=0, if(k!=c[i], return(0)))); return(1)

%Y Cf. A050278, A082810, A261315.

%K nonn,base,easy

%O 1,3

%A _Felix Fröhlich_, Dec 26 2015