A118939 Primes p such that (p^2+3)/4 is prime.

3, 5, 7, 11, 13, 17, 29, 31, 41, 43, 67, 83, 101, 109, 139, 151, 157, 179, 181, 199, 211, 223, 239, 263, 277, 283, 307, 311, 337, 347, 353, 379, 389, 419, 431, 463, 491, 557, 577, 587, 619, 659, 673, 739, 757, 797, 809, 811, 829, 853, 907, 911, 953, 991, 1051

Offset

1,1

Comments

For all primes q>2, we have q=4k+-1 for some k, which makes it easy to show that 4 divides q^2+3. Similar sequences, with p and (p^2+a)/b both prime, are A048161, A062324, A062326, A062718, A109953, A110589, A118915, A118918, A118940, A118941 and A118942.

Links

Table of n, a(n) for n=1..55.

Mathematica

Select[Prime[Range[200]], PrimeQ[(#^2+3)/4]&]

Crossrefs

Sequence in context: A020628 A108816 A088503 * A239391 A087382 A355845

Adjacent sequences: A118936 A118937 A118938 * A118940 A118941 A118942

Keyword

nonn

Author

T. D. Noe, May 06 2006

Status

approved