login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 59th year, we have over 358,000 sequences, and we’ve crossed 10,300 citations (which often say “discovered thanks to the OEIS”).

Other ways to Give
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A094712 Primes that are not the sum of three positive squares. 3
2, 5, 7, 13, 23, 31, 37, 47, 71, 79, 103, 127, 151, 167, 191, 199, 223, 239, 263, 271, 311, 359, 367, 383, 431, 439, 463, 479, 487, 503, 599, 607, 631, 647, 719, 727, 743, 751, 823, 839, 863, 887, 911, 919, 967, 983, 991 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Except for primes 2, 5, 13 and 37, this sequence consists all primes p such that p = 7 (mod 8). The density of these primes is 0.25.

LINKS

Chai Wah Wu, Table of n, a(n) for n = 1..10000

MATHEMATICA

lst={}; lim=32; Do[n=a^2+b^2+c^2; If[n<lim^2 && PrimeQ[n], lst=Union[lst, {n}]], {a, lim}, {b, a, Sqrt[lim^2-a^2]}, {c, b, Sqrt[lim^2-a^2-b^2]}]; Complement[Prime[Range[PrimePi[lst[[ -1]]]]], lst]

CROSSREFS

Cf. A085317 (primes that are the sum of three positive squares).

Sequence in context: A045355 A252281 A165319 * A095281 A106889 A155028

Adjacent sequences: A094709 A094710 A094711 * A094713 A094714 A094715

KEYWORD

nonn

AUTHOR

T. D. Noe, May 21 2004

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified December 6 04:57 EST 2022. Contains 358594 sequences. (Running on oeis4.)