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A045817 Numbers n written in base 7, where in the list of divisors of n (in base 7), each digit 0-6 appears equally often.

%I A045817 #16 Sep 08 2018 04:22:53
%S A045817 3602,246506,264533,266405,303652,320556,324255,325605,342560,345064,
%T A045817 345406,345604,346340,362055,414056,430462,434630,435065,436430,
%U A045817 436550,453605,500426,500641,506022,524360,524406,526433,530632,532650,533402
%N A045817 Numbers n written in base 7, where in the list of divisors of n (in base 7), each digit 0-6 appears equally often.
%H A045817 Robert Israel, <a href="/A045817/b045817.txt">Table of n, a(n) for n = 1..161</a>
%H A045817 N. Nomoto, <a href="http://www.geocities.co.jp/Technopolis/1793/09digit.htm">In the list of divisors of n,... </a> [broken link]
%e A045817 E.g., divisors of 342560 (base 7) are (1,2,10,20,15463,34256,154630,342560) (all in base 7); the numbers of digits (0-6) are [0(4),1(4),2(4),3(4),4(4),5(4),6(4)].
%p A045817 N:= 7^6:
%p A045817 cv7:= proc(n) local L; L:= convert(n,base,7);
%p A045817 add(L[i]*10^(i-1),i=1..nops(L)) end proc:
%p A045817 V:= Matrix(N,7,datatype=integer[8]):
%p A045817 count:= 0: Res:= NULL:
%p A045817 for i from 1 to N do
%p A045817   L:= convert(i,base,7);
%p A045817   M:= Vector[row]([seq(numboccur(d,L),d=0..6)],datatype=integer[8]);
%p A045817   for r from i to N by i do V[r,..]:= V[r,..] + M od;
%p A045817   if nops(convert(V[i,..],set))=1 then
%p A045817     count:= count+1;
%p A045817     w:= cv7(i);
%p A045817     Res:= Res,w;
%p A045817   fi
%p A045817 od:
%p A045817 Res; # _Robert Israel_, Sep 07 2018
%Y A045817 Cf. A038564, A038565, A045818.
%K A045817 easy,nonn,base
%O A045817 1,1
%A A045817 _Naohiro Nomoto_
%E A045817 Definition clarified by _Robert Israel_, Sep 07 2018