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A121825 Primes of the form 4*k^2 + 3. 1
3, 7, 19, 67, 103, 199, 487, 787, 1447, 2503, 2707, 3847, 4099, 4903, 5479, 5779, 8467, 8839, 11239, 12547, 14887, 16903, 17959, 19603, 21319, 23719, 24967, 25603, 29587, 31687, 47527, 52903, 58567, 59539, 61507, 65539, 75079, 81799, 88807, 92419 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

See also A121326 (Primes of the form 4*k^2 + 1); see also A049423 (Primes of the form k^2 + 3). For the primes of the form 4*k^2 + 3, the corresponding values of k are 1, 2, 4, 5, 7, 11, 14, 19, 25, 26, 31, 32, 35, 37, 38, 46, 47, 53, 56, 61, 65, 67, 70, 73.

LINKS

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

FORMULA

a(n) = 3 + (2*A097697(n))^2. - R. J. Mathar, Aug 07 2008

PROG

(MAGMA) [ a: n in [0..200] | IsPrime(a) where a is 4*n^2+3 ]; // Vincenzo Librandi, Dec 22 2010

CROSSREFS

Cf. A000040, A002496, A049423, A121326.

Sequence in context: A160128 A051139 A049423 * A066237 A135741 A328159

Adjacent sequences:  A121822 A121823 A121824 * A121826 A121827 A121828

KEYWORD

easy,nonn

AUTHOR

Jonathan Vos Post, Aug 27 2006

EXTENSIONS

Terms after 21319 added by R. J. Mathar, Aug 07 2008

3 added by Vincenzo Librandi, Dec 22 2010

STATUS

approved

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Last modified September 27 09:09 EDT 2020. Contains 337380 sequences. (Running on oeis4.)