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A088619 Numbers n such that the concatenation of 1, n and n^2 is prime. 2
3, 11, 21, 29, 39, 47, 59, 69, 101, 111, 131, 149, 171, 183, 197, 213, 231, 243, 249, 251, 297, 299, 317, 323, 329, 369, 387, 401, 411, 423, 431, 461, 501, 521, 527, 533, 537, 539, 543, 593, 651, 657, 669, 717, 741, 743, 779, 819, 867, 869, 873, 897, 939, 981 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

EXAMPLE

3 is a member as 139 is a prime. 11 is a member as 111121 (concatenation of 1,11 and 121) is prime.

MATHEMATICA

Select[ Range[1000], PrimeQ[ FromDigits[ Join[ IntegerDigits[ #^0], IntegerDigits[ # ], IntegerDigits[ #^2]]]] &]

CROSSREFS

Cf. A068702.

Sequence in context: A139221 A006876 A031239 * A031318 A082485 A064568

Adjacent sequences:  A088616 A088617 A088618 * A088620 A088621 A088622

KEYWORD

base,nonn

AUTHOR

Amarnath Murthy (amarnath_murthy(AT)yahoo.com), Oct 17 2003

EXTENSIONS

Edited and extended by Robert G. Wilson v (rgwv(AT)rgwv.com) and Ray Chandler (rayjchandler(AT)sbcglobal.net), Oct 18 2003

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Last modified February 14 23:16 EST 2012. Contains 205687 sequences.