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A119178 Triangular numbers composed of digits {2,7,8}. 2
28, 78, 2278, 8778, 222778, 828828, 887778, 8272278, 22227778, 88278828, 88877778, 2222277778, 2882872278, 8882778828, 8888777778, 222222777778, 888827778828, 888887777778, 22222227777778, 88888277778828, 88888877777778, 228887828777278, 272277272227278 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
Table of n, a(n) for n=1..23.
Giovanni Resta, Tridigital Triangular Numbers
FORMULA
a(n) = A000217(A119179(n)). - Michel Marcus, Mar 22 2023
CROSSREFS
Cf. A000217, A119179. See A119033 for a table of cross-references.
Sequence in context: A044166 A044547 A268733 * A161935 A039415 A043238
Adjacent sequences: A119175 A119176 A119177 * A119179 A119180 A119181
KEYWORD
nonn,base
AUTHOR
Giovanni Resta, May 10 2006
EXTENSIONS
a(21)-a(23) from Tyler Busby, Mar 22 2023
STATUS
approved

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Last modified May 17 10:20 EDT 2024. Contains 372594 sequences. (Running on oeis4.)