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A158361 Primes p with property that Q=p^4+2^4 is prime 1
3, 5, 7, 11, 17, 19, 23, 37, 41, 59, 61, 71, 79, 97, 131, 139, 179, 223, 227, 229, 241, 283, 313, 317, 359, 367, 379, 383, 389, 439, 449, 461, 487, 503, 521, 569, 593, 617, 619, 631, 661, 683, 709, 733, 811, 821, 853, 911, 977, 1049, 1061, 1063, 1069, 1091, 1093, 1117 (list; graph; refs; listen; history; internal format)
OFFSET

1,1

COMMENTS

Q is always congruent to 1 (mod 4)

Q is divisible by 17 if p is congruent to 1, 4, 13, or 16 (mod 17)

It is conjectured that sequence a(n) is infinite

REFERENCES

Leonard E. Dickson, History of the Theory of numbers, vol. I, Dover Publications 2005

Richard Guy, "Unsolved Problems in Number Theory"

EXAMPLE

3 is in the sequence since for p=3: p^4+2^4 = 3^4+16 = 97 is prime

29 is not in the sequence since 29^4+2^4 = 707297 = 73 x 9689 is not prime

PROG

(PARI) isA158361(n) = isprime(n) && isprime(n^4+16)

CROSSREFS

Cf. A062324 A157950 A157764.

Sequence in context: A085498 A128926 A139559 * A048184 A163420 A155489

Adjacent sequences:  A158358 A158359 A158360 * A158362 A158363 A158364

KEYWORD

nonn

AUTHOR

Ulrich Krug (leuchtfeuer37(AT)gmx.de), Mar 17 2009

EXTENSIONS

Corrected and edited by Michael Porter (michael_b_porter(AT)yahoo.com), Dec 17 2009

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Last modified February 17 11:46 EST 2012. Contains 206011 sequences.