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%I #11 Jul 01 2019 05:44:22
%S 1,2,3,4,5,7,43,146,365,438,443,803,887,2221,4442,6663,8887,87876,
%T 88183,153837,250244,285597,292860,296294,302877,307674,344268,351612,
%U 380718,403398,423260,441821,444443,550238,579038,584438,588974,593163,600363
%N Numbers n such that sum of divisors of these numbers gives a decimal repdigit.
%H Giovanni Resta, <a href="/A096841/b096841.txt">Table of n, a(n) for n = 1..365</a>
%e n=43:sigma[43]=44; regular solutions:repdigit-1=prime.
%t rd[x_] := Length[Union[IntegerDigits[x]]] Do[s = rd[DivisorSigma[1, n]]; s1 = DivisorSigma[1, n]; If[Equal[s, 1], Print[{n, s1}]; ta[[u]] = n; u = u + 1], {n, 1, 1000000}];ta;DivisorSigma[1, ta]
%t Select[Range[650000],Length[Union[IntegerDigits[DivisorSigma[1,#]]]]==1&] (* _Harvey P. Dale_, May 11 2019 *)
%Y Cf. A096503-A096508, A096841-A096846, A000203.
%K base,nonn
%O 1,2
%A _Labos Elemer_, Jul 15 2004
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