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A079797 Products of two primes p and q such that (p*q)^2 + p^2 - q^2 and (p*q)^2 - p^2 + q^2 are both prime. 1
6, 14, 22, 33, 35, 38, 62, 69, 74, 85, 115, 119, 146, 159, 214, 219, 237, 267, 301, 335, 339, 469, 511, 519, 537, 542, 559, 566, 573, 591, 597, 634, 718, 721, 737, 794, 803, 851, 878, 917, 933, 1003, 1007, 1042, 1059, 1099, 1219, 1226, 1241, 1271, 1294, 1299 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

COMMENTS

The two primes generated from p and q are sometimes called flip-flap twin primes. There is probably an infinity of them.

EXAMPLE

a(2) = 14 since (2*7)^2 + 2^2 - 7^2 = 151 and (2*7)^2 - 2^2 + 7^2 = 241 are both primes.

CROSSREFS

Sequence in context: A189785 A017137 A190522 * A093380 A123228 A015832

Adjacent sequences:  A079794 A079795 A079796 * A079798 A079799 A079800

KEYWORD

easy,nonn

AUTHOR

Olivier Gerard (olivier.gerard(AT)gmail.com), Feb 19 2003

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Last modified February 17 16:13 EST 2012. Contains 206050 sequences.