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Triangular numbers which have one or more occurrences of exactly ten different digits.
7

%I #17 Jul 26 2014 16:40:41

%S 1062489753,1239845706,1256984730,1520843976,1539264870,1597283460,

%T 1684930275,1952843760,1957346028,1978236450,2197480365,2367098415,

%U 2418079653,2503948761,2634980715,2718609453,2735891406,2750483196,2764518903,2854316790,2915768430

%N Triangular numbers which have one or more occurrences of exactly ten different digits.

%C The first term having a repeated digit is a(83) = 10075823946.

%C Superset of A115940. - _R. J. Mathar_, May 02 2014

%H Charles R Greathouse IV, <a href="/A241812/b241812.txt">Table of n, a(n) for n = 1..10000</a>

%t Select[Table[(n(n+1))/2,{n,45000,100000}],Min[DigitCount[#]]>0&] (* _Harvey P. Dale_, Jul 26 2014 *)

%o (PARI) s=[]; for(n=0, 100000, if(#vecsort(eval(Vec(Str(n*(n+1)/2))), , 8)==10, s=concat(s, n*(n+1)/2))); s

%Y Cf. A045914, A062691, A162304, A241787, A241788, A241789, A241790, A241791, A241792, A000217.

%K nonn,base,easy

%O 1,1

%A _Colin Barker_, Apr 29 2014