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A369105
Primes p such that p+2 has only prime factors congruent to -1 modulo 4.
5
5, 7, 17, 19, 29, 31, 41, 47, 61, 67, 79, 97, 101, 127, 131, 137, 139, 149, 197, 199, 211, 229, 241, 251, 269, 277, 281, 307, 359, 379, 397, 421, 439, 461, 467, 487, 499, 521, 569, 571, 587, 601, 617, 619, 631, 641, 647, 691, 709, 719, 727, 751, 757, 787, 809, 811
OFFSET
1,1
COMMENTS
Jones and Zvonkin call these primes BCC primes, where BCC stands for Bujalance, Cirre, and Conder.
LINKS
E. Bujalance, F. J. Cirre, and M. D. E. Conder, Bounds on the orders of groups of automorphisms of a pseudo-real surface of given genus, Journal of the London Mathematical Society, Volume 101, Issue 2, p. 877-906, (2019).
Gareth A. Jones and Alexander K. Zvonkin, A number-theoretic problem concerning pseudo-real Riemann surfaces, arXiv:2401.00270 [math.NT], 2023. See page 1.
MATHEMATICA
Select[Prime[Range[150]], PrimeQ[f=First/@FactorInteger[#+2]] == Table[True, {j, PrimeNu[#+2]}] && Mod[f, 4] == Table[3, {m, PrimeNu[#+2]}] &]
PROG
(PARI) is1(n) = {my(p = factor(n)[, 1]); for(i = 1, #p, if(p[i] % 4 == 1, return(0))); 1; };
lista(pmax) = forprime(p = 3, pmax, if(is1(p+2), print1(p, ", "))); \\ Amiram Eldar, Jun 03 2024
KEYWORD
nonn
AUTHOR
Stefano Spezia, Jan 13 2024
STATUS
approved