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A119154 Triangular numbers composed of digits {2,3,6}. 2
3, 6, 36, 66, 666, 22366, 333336, 23232336, 336662326, 2232222336, 3263633236, 6266233326, 262322266326, 266633626626, 2263263223266, 36226633633326, 66333362366236266, 3236622262232626626666, 3322222636222323322336 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..19.

G. Resta, Tridigital Triangular Numbers

MATHEMATICA

Select[Flatten[Table[FromDigits/@Tuples[{2, 3, 6}, n], {n, 10}]], OddQ[Sqrt[8#+1]]&] (* The program generates the first 12 terms of the sequence. To generate more, increase the constant after "n, " but the program will take longer to run. *) (* Harvey P. Dale, Apr 18 2020 *)

CROSSREFS

Cf. A000217, A058458, A119155. See A119033 for a table of cross-references.

Sequence in context: A119115 A079653 A119063 * A119194 A119198 A119196

Adjacent sequences:  A119151 A119152 A119153 * A119155 A119156 A119157

KEYWORD

nonn,base

AUTHOR

Giovanni Resta, May 10 2006

STATUS

approved

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Last modified October 18 06:50 EDT 2021. Contains 348066 sequences. (Running on oeis4.)