A241789 Triangular numbers which have one or more occurrences of exactly six different digits.

102378, 103285, 104653, 106953, 108345, 109278, 109746, 120786, 124750, 132870, 135460, 137026, 138075, 150426, 152076, 154290, 158203, 162735, 168490, 170236, 174936, 178503, 189420, 190653, 194376, 197506, 198765, 203841, 205761, 215496, 219453, 231540

Offset: 1

Author

Colin Barker, Apr 28 2014

Keywords

• nonn
• base

Comments

The first term having a repeated digit is 1004653.

Links

• Colin Barker, Table of n, a(n) for n = 1..2500

Crossrefs

Cf. A045914, A062691, A162304, A241787, A241788, A241790, A241791, A241792, A241812.

Cf. A000217.

Programs

Mathematica

Select[Table[(n(n+1))/2,{n,447,681}],Length[Union[ IntegerDigits[ #]]] == 6&] (* Harvey P. Dale, Feb 17 2018 *)

PARI

s=[]; for(n=0, 800, if(#vecsort(eval(Vec(Str(n*(n+1)/2))), , 8)==6, s=concat(s, n*(n+1)/2))); s