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A119172
Triangular numbers composed of digits {2,6,7}.
2
6, 66, 276, 666, 7626, 6666726, 77666666626, 2662627722726, 2777672627676766, 77772662277672726, 6622726277766676626, 672667762262676277666726
OFFSET
1,1
COMMENTS
a(13) > 10^40. - Tyler Busby, Mar 29 2023
FORMULA
a(n) = A000217(A119173(n)). - Tyler Busby, Mar 29 2023
CROSSREFS
Cf. A000217, A058462, A119173. See A119033 for a table of cross-references.
Sequence in context: A133424 A045641 A071276 * A064167 A175455 A185253
KEYWORD
nonn,base,more
AUTHOR
Giovanni Resta, May 10 2006
STATUS
approved