%I #10 Jun 20 2021 16:15:44
%S 0,1,3,6,10,15,21,28,36,45,78,91,105,120,136,153,171,190,210,231,253,
%T 276,325,351,378,406,435,465,496,528,561,595,630,703,741,780,820,861,
%U 903,946,1035,1081,1275,1326,1378,1431,1485,1540,1596,1653,1830,1891
%N Triangular numbers whose decimal expansion contains no pair of consecutive equal digits.
%C For indices, see A050759.
%H Harvey P. Dale, <a href="/A050760/b050760.txt">Table of n, a(n) for n = 1..1000</a>
%t Select[Accumulate[Range[0,70]],FreeQ[Differences[IntegerDigits[#]],0]&] (* _Harvey P. Dale_, Jun 20 2021 *)
%Y Cf. A043096, A000217, A050759.
%K nonn,base
%O 1,3
%A _Patrick De Geest_, Sep 15 1999
%E Offset changed to 1 by _Jon E. Schoenfield_, Oct 18 2019
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