

A061275


Smaller of two consecutive primes whose sum is a square.


16



17, 47, 71, 283, 881, 1151, 1913, 2591, 3527, 4049, 6047, 7193, 7433, 15137, 20807, 21617, 24197, 26903, 28793, 34847, 46817, 53129, 56443, 69191, 74489, 83231, 84047, 98563, 103049, 103967, 109507, 110441, 112337, 136237, 149057, 151247
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OFFSET

1,1


LINKS

Harry J. Smith, Table of n, a(n) for n = 1..1000


EXAMPLE

a(4) = 283, the next prime is 293 and 283 + 293 = 576 = 24^2.


MATHEMATICA

Transpose[Select[Partition[Prime[Range[20000]], 2, 1], IntegerQ[Sqrt[Plus@@# ]]&]][[1]] (* Harvey P. Dale, Aug 04 2009 *)


PROG

(PARI) { default(primelimit, 550655327); n=0; q=2; forprime (p=3, 550655327, if (issquare(p+q), write("b061275.txt", n++, " ", q)); q=p ) } \\ Harry J. Smith, Jul 20 2009


CROSSREFS

Subset of A091624.
Cf. A206279, A206280, A206281.
Sequence in context: A275770 A126912 A051616 * A128468 A031374 A201792
Adjacent sequences: A061272 A061273 A061274 * A061276 A061277 A061278


KEYWORD

nonn,easy


AUTHOR

Amarnath Murthy, Apr 25 2001


EXTENSIONS

More terms from Larry Reeves (larryr(AT)acm.org) and Asher Natan Auel (auela(AT)reed.edu), May 15 2001
Offset changed from 0 to 1 by Harry J. Smith, Jul 20 2009


STATUS

approved



