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%I #12 May 27 2023 18:40:05
%S 6,66,276,666,7626,6666726,77666666626,2662627722726,2777672627676766,
%T 77772662277672726,6622726277766676626,672667762262676277666726
%N Triangular numbers composed of digits {2,6,7}.
%C a(13) > 10^40. - _Tyler Busby_, Mar 29 2023
%H Giovanni Resta, <a href="http://www.numbersaplenty.com/tr/tr267.html">Tridigital Triangular Numbers</a>.
%F a(n) = A000217(A119173(n)). - _Tyler Busby_, Mar 29 2023
%Y Cf. A000217, A058462, A119173. See A119033 for a table of cross-references.
%K nonn,base,more
%O 1,1
%A _Giovanni Resta_, May 10 2006