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%I #12 Mar 29 2023 17:51:33
%S 6,66,496,666,946,4699966666944446964496
%N Triangular numbers composed of digits {4,6,9}.
%C a(7) > 10^40. - _Tyler Busby_, Mar 29 2023
%H Giovanni Resta, <a href="http://www.numbersaplenty.com/tr/tr469.html">Tridigital Triangular Numbers</a>.
%F a(n) = A000217(A119215(n)). - _Michel Marcus_, Mar 27 2023
%Y Cf. A000217, A053961, A119215. See A119033 for a table of cross-references.
%K nonn,base,more
%O 1,1
%A _Giovanni Resta_, May 10 2006