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

%I #15 Feb 09 2019 12:57:02

%S 10348975,10623745,10725396,10869453,10934826,12347965,12357906,

%T 12487503,12647935,12673095,12784096,13862745,14756028,14826735,

%U 15237960,15298746,15304278,15879430,16247850,16384950,17084935,17502486,17543926,17829406

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

%C The first term having a repeated digit is 100642578.

%H Colin Barker, <a href="/A241791/b241791.txt">Table of n, a(n) for n = 1..2000</a>

%t Select[Accumulate[Range[7000]],Length[Union[IntegerDigits[#]]]==8&] (* _Harvey P. Dale_, Feb 09 2019 *)

%o (PARI) s=[]; for(n=0, 7000, if(#vecsort(eval(Vec(Str(n*(n+1)/2))), , 8)==8, s=concat(s, n*(n+1)/2))); s

%Y Cf. A045914, A062691, A162304, A241787, A241788, A241789, A241790, A241792, A241812.

%Y Cf. A000217.

%K nonn,base

%O 1,1

%A _Colin Barker_, Apr 28 2014