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A119149
Numbers k such that the k-th triangular number contains only digits {1,7,9}.
2
1, 13, 18, 58, 586, 1258, 58613, 1350538, 1414213, 59517693, 1398413386, 5996665693, 119976657489461, 12642721051982282188058, 59853148952744518364458
(list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
LINKS
Table of n, a(n) for n=1..15.
Giovanni Resta, Tridigital Triangular Numbers
CROSSREFS
Cf. A000217, A119148. See A119034 for a table of cross-references.
Sequence in context: A318348 A197704 A218626 * A217658 A372763 A388990
Adjacent sequences: A119146 A119147 A119148 * A119150 A119151 A119152
KEYWORD
nonn,base,more
AUTHOR
Giovanni Resta, May 10 2006
EXTENSIONS
a(14)-a(15) from Bert Dobbelaere, Mar 15 2026
STATUS
approved

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Last modified May 21 20:59 EDT 2026. Contains 395806 sequences.
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