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A119205
Numbers k such that the k-th triangular number contains only digits {4,5,7}.
2
9, 10, 3390, 38589, 12453549, 3080826336474, 298253071929010, 33089502135135685
(list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
LINKS
Table of n, a(n) for n=1..8.
Giovanni Resta, Tridigital Triangular Numbers.
CROSSREFS
Cf. A000217, A119204. See A119034 for a table of cross-references.
Sequence in context: A042191 A042729 A156292 * A119207 A165254 A058069
Adjacent sequences: A119202 A119203 A119204 * A119206 A119207 A119208
KEYWORD
nonn,base,more
AUTHOR
Giovanni Resta, May 10 2006
EXTENSIONS
a(8) from Tyler Busby, Mar 31 2023
STATUS
approved

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Last modified November 16 09:33 EST 2024. Contains 377785 sequences.
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