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A137066 Numbers n such that n and the square of n use only the digits 2, 3, 4 and 5. 1
2, 5, 235, 2335, 23335, 233335, 2333335, 2354235, 23333335, 233333335, 2333333335, 2333524235, 23333333335, 23333524235, 233333333335, 2333333333335, 23333333333335, 233333333333335 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Generated with DrScheme.

Contains 2*10^n + (10^n-1)/3 + 2 for n >= 2. Are these all the terms > 23333524235? There are no others with up to 25 digits. - Robert Israel, Jul 02 2018

LINKS

Table of n, a(n) for n=1..18.

J. Wellons, Tables of Shared Digits

EXAMPLE

23333524235^2 = 544453353225332335225.

PROG

(PARI) isokd(x) = (x < 2) || (x > 5);

isok(n) = !#select(x->isokd(x), digits(n)) && !#select(x->isokd(x), digits(n^2)); \\ Michel Marcus, Jul 02 2018

CROSSREFS

Sequence in context: A249180 A135724 A137068 * A175977 A121270 A085603

Adjacent sequences:  A137063 A137064 A137065 * A137067 A137068 A137069

KEYWORD

base,nonn

AUTHOR

Jonathan Wellons (wellons(AT)gmail.com), Jan 22 2008

STATUS

approved

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Last modified April 5 03:15 EDT 2020. Contains 333238 sequences. (Running on oeis4.)