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A007520 Primes == 3 (mod 8).
(Formerly M2882)
25
3, 11, 19, 43, 59, 67, 83, 107, 131, 139, 163, 179, 211, 227, 251, 283, 307, 331, 347, 379, 419, 443, 467, 491, 499, 523, 547, 563, 571, 587, 619, 643, 659, 683, 691, 739, 787, 811, 827, 859, 883, 907, 947, 971, 1019, 1051, 1091, 1123, 1163, 1171, 1187 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Primes of the form 3x^2+2xy+3y^2 with x and y in Z. - T. D. Noe, May 07 2005

Also, primes of the form X^2+2Y^2, X=|x-y|, Y=x+y. - Moshe Levin, Dec 06 2011

Sum of no fewer than three positive squares.

Smallest terms expressible as sum of three distinct positive squares: 59=1^2+3^2+7^2, 83=3^2+5^2+7^2, 107, 131, 139, 179, 211, 227, 251, 283, 307. - Moshe Levin, Dec 06 2011

REFERENCES

N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).

LINKS

T. D. Noe, Table of n, a(n) for n = 1..1000

M. Abramowitz and I. A. Stegun, eds., Handbook of Mathematical Functions, National Bureau of Standards, Applied Math. Series 55, Tenth Printing, 1972 [alternative scanned copy].

MATHEMATICA

lst={}; Do[p=8*n+3; If[PrimeQ[p], AppendTo[lst, p]], {n, 0, 10^3}]; lst [From Vladimir Joseph Stephan Orlovsky, Aug 22 2008]

p=3; k=0; nn=1000; Reap[While[k<nn, If[PrimeQ[p], k++; Sow[p]]; p=p+8]][[2, 1]] (* Moshe Levin, Dec 06 2011 *)

PROG

(PARI) forprime(p=2, 97, if(p%8==3, print1(p", "))) \\ Charles R Greathouse IV, Aug 17 2011

(MAGMA) [p: p in PrimesUpTo(2000) | p mod 8 eq 3]; // Vincenzo Librandi, Aug 07 2012

CROSSREFS

Sequence in context: A079544 A192717 A163183 * A213891 A163851 A213051

Adjacent sequences:  A007517 A007518 A007519 * A007521 A007522 A007523

KEYWORD

nonn,easy

AUTHOR

N. J. A. Sloane, Robert G. Wilson v

STATUS

approved

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Last modified December 22 02:01 EST 2014. Contains 252326 sequences.