A125283 Primes p for which there exists no integer n with 1 < n^2 < p such that n^4 - n^2 + p is prime (i.e., primes that don't arise as q's in A126769).

2, 3, 13, 103, 131

Offset

1,1

Comments

Sequence suggested by W. Edwin Clark.

Is this sequence finite?

Primes not in A126769 are listed in A128292.

Next term >= 5*10^7. - Klaus Brockhaus, Mar 15 2007

Next term > 2*10^9. - Jon E. Schoenfield, Apr 06 2018

Links

Table of n, a(n) for n=1..5.

Mathematica

fQ[p_] := Block[{r = Rest@Range@Floor@Sqrt@p}, Union@ PrimeQ[r^4 - r^2 + p] == {False}]; lst = {2, 3}; Do[ If[ fQ@ Prime@n, AppendTo[lst, Prime@n]], {n, 3, 10^5}]; lst (* Robert G. Wilson v, Mar 01 2007 *)

Crossrefs

Cf. A126769.

Sequence in context: A361520 A068096 A098462 * A098406 A280012 A224792

Adjacent sequences: A125280 A125281 A125282 * A125284 A125285 A125286

Keyword

nonn,more

Author

Tomas Xordan, Feb 25 2007

Status

approved