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A218397 Triangular numbers composed of digits {0,2,7}. 2
70007020020, 27272070272700, 20720272227227700077007700020, 22200020770272007007202277772702722200 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

No other terms below 10^40.

LINKS

Table of n, a(n) for n=1..4.

G. Resta, Tridigital Triangular Numbers

FORMULA

a(n) = A000217(A218398(n))

CROSSREFS

Cf. A000217, A218398. See A119033 for a table of cross-references.

Sequence in context: A139572 A321284 A186095 * A103617 A213334 A211417

Adjacent sequences:  A218394 A218395 A218396 * A218398 A218399 A218400

KEYWORD

base,nonn,more

AUTHOR

Max Alekseyev, Oct 28 2012

STATUS

approved

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Last modified September 22 10:58 EDT 2020. Contains 337289 sequences. (Running on oeis4.)