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 A241787 Triangular numbers which have one or more occurrences of exactly four different digits. 7

%I

%S 1035,1275,1326,1378,1485,1540,1596,1653,1830,1953,2016,2145,2346,

%T 2415,2485,2701,2850,3081,3160,3240,3486,3570,3741,3916,4095,4186,

%U 4278,4371,4560,4753,4851,4950,5460,5671,6105,6328,6903,7021,7140,7260,7381,7503,8256

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

%C The first term having a repeated digit is 10153.

%H Colin Barker, <a href="/A241787/b241787.txt">Table of n, a(n) for n = 1..2000</a>

%o (PARI) s=[]; for(n=0, 300, if(#vecsort(eval(Vec(Str(n*(n+1)/2))), , 8)==4, s=concat(s, n*(n+1)/2))); s

%Y Cf. A045914, A062691, A162304, A241788, A241789, A241790, A241791, A241792, A241812.

%Y Cf. A000217.

%K nonn,base

%O 1,1

%A _Colin Barker_, Apr 28 2014

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Last modified June 17 16:48 EDT 2021. Contains 345085 sequences. (Running on oeis4.)