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A302485
Primes p not of the form k^2+s where k > 1 and 1 <= s < (k+1)^2, such that q = k^4+s is prime.
0
2, 3, 13, 19, 73, 103, 113, 131, 223, 293, 313, 461, 761, 863, 1013, 1069, 1171, 1223, 2293, 2711, 2887, 2903, 4583, 5623, 6949, 7151, 7873, 8563, 8803, 12413, 13613, 16703, 17393, 22013, 24733, 28723
OFFSET
1,1
COMMENTS
No more terms <= 10^8. Is this sequence finite?
PROG
(PARI) upto(n) = {my(res = List([2, 3]), b); forprime(p = 5, n, b = 0; for(k = ceil(sqrt(p / 2 + 1/4) - 0.5), sqrtint(p-1), if(isprime(k^4 + p - k^2), b = 1; next(1))); if(!b, listput(res, p))); res}
CROSSREFS
Primes not in A124598.
Sequence in context: A374823 A368396 A103087 * A135118 A274905 A234366
KEYWORD
nonn,more
AUTHOR
David A. Corneth, Apr 08 2018
STATUS
approved