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A167724
Squares that becomes a prime number when prefixed with a 9.
1
1369, 2401, 2809, 3481, 5929, 9409, 10201, 14161, 16129, 17689, 25921, 28561, 32761, 41209, 44521, 64009, 94249, 100489, 108241, 116281, 117649, 130321, 137641, 146689, 157609, 170569, 175561, 177241, 196249, 201601, 218089, 219961
OFFSET
1,1
COMMENTS
Subsequence of squares of A032672. - Michel Marcus, Jun 22 2016
LINKS
MATHEMATICA
Select[Range[1, 500000, 2]^2, PrimeQ[FromDigits[Join[{9}, IntegerDigits[#]]]] &] (* G. C. Greubel, Jun 21 2016 *)
CROSSREFS
Cf. A032672.
Sequence in context: A192823 A221932 A331464 * A156574 A145697 A045107
KEYWORD
base,nonn
AUTHOR
Claudio Meller, Nov 10 2009
STATUS
approved