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A126118 Primes of the form a^2 + b^2 + c^2 such that a^4 + b^4 + c^4 is prime as well and larger than the first one. 0
101, 107, 149, 173, 179, 251, 389, 521, 701, 1097, 1601, 1613, 1901, 1907, 2549, 2897, 2909, 3701, 4133, 4139, 5051, 6101, 7229, 7817, 7829, 8429, 10457, 11171, 11933, 12689, 13499, 15131, 15149, 16883, 18749, 19697, 20693, 21701, 22721, 22739 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

With a=b=1 and c=0, both a^2 + b^2 + c^2 and a^4 + b^4 + c^4 would yield 2 (a prime); similarly, with a=b=c=1, both sums would yield 3 (also a prime). Thus, without the "larger than the first one" constraint, both 2 and 3 would be terms of this sequence. - Jon E. Schoenfield, Jun 15 2021

LINKS

Table of n, a(n) for n=1..40.

EXAMPLE

101 = 1^2 + 6^2 + 8^2 and 5393 = 1^4 + 6^4 + 8^4 is prime as well.

31859 = 99^2 + 103^2 + 107^2 and 339690083 = 99^4 + 103^4 + 107^4 is prime as well.

CROSSREFS

Sequence in context: A111348 A081649 A344802 * A118773 A092628 A107219

Adjacent sequences:  A126115 A126116 A126117 * A126119 A126120 A126121

KEYWORD

nonn

AUTHOR

Tomas Xordan, Mar 05 2007

STATUS

approved

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Last modified November 30 21:20 EST 2021. Contains 349426 sequences. (Running on oeis4.)