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A057659 Prime numbers whose square is composed of just two different decimal digits. 0
5, 7, 11, 109, 173, 81619 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

COMMENTS

Conjectured to be a finite sequence.

No further terms up to Prime[1000000]=15485863  [From Harvey P. Dale, Mar 20 2011]

REFERENCES

Related to the Unsolved problem F24, p. 262, of the UPiNT by R. K. Guy

LINKS

Table of n, a(n) for n=0..5.

EXAMPLE

Example: 81619^2 = 6661661161

MATHEMATICA

Select[Prime[Range[10000]], Count[DigitCount[#^2], 0] ==8&] (* Harvey P. Dale, Mar 20 2011 *)

CROSSREFS

Sequence in context: A086140 A104387 A133761 * A098040 A263880 A082565

Adjacent sequences:  A057656 A057657 A057658 * A057660 A057661 A057662

KEYWORD

easy,nonn,base

AUTHOR

Carlos Rivera, Oct 15 2000

STATUS

approved

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Last modified August 1 00:13 EDT 2021. Contains 346377 sequences. (Running on oeis4.)