cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

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A296935 Rational primes that decompose in the field Q(sqrt(11)).

Original entry on oeis.org

5, 7, 19, 37, 43, 53, 79, 83, 89, 97, 107, 113, 127, 131, 137, 139, 151, 157, 167, 181, 211, 227, 229, 239, 257, 263, 269, 271, 283, 307, 313, 317, 347, 353, 359, 389, 397, 401, 421, 431, 433, 439, 449, 479, 491, 503, 509, 521, 523, 547, 563, 571, 577, 607
Offset: 1

Views

Author

N. J. A. Sloane, Dec 26 2017

Keywords

Crossrefs

Programs

  • Maple
    Load the Maple program HH given in A296920. Then run HH(11, 200); This produces A296935, A296936, A038881, A038882.
  • Mathematica
    Select[Prime[Range[120]], KroneckerSymbol[11, #] == 1 &] (* Amiram Eldar, Dec 24 2023 *)
  • PARI
    list(lim)=my(v=List()); forprime(p=5,lim, if(kronecker(11,p)==1, listput(v,p))); Vec(v) \\ Charles R Greathouse IV, Mar 18 2018

A296937 Rational primes that decompose in the field Q(sqrt(13)).

Original entry on oeis.org

3, 17, 23, 29, 43, 53, 61, 79, 101, 103, 107, 113, 127, 131, 139, 157, 173, 179, 181, 191, 199, 211, 233, 251, 257, 263, 269, 277, 283, 311, 313, 337, 347, 367, 373, 389, 419, 433, 439, 443, 467, 491, 503, 521, 523, 547, 563, 569, 571, 599, 601, 607, 641
Offset: 1

Views

Author

N. J. A. Sloane, Dec 26 2017

Keywords

Comments

Is this the same sequence as A141188 or A038883? - R. J. Mathar, Jan 02 2018
From Jianing Song, Apr 21 2022: (Start)
Primes p such that Kronecker(13, p) = Kronecker(p, 13) = 1, where Kronecker() is the Kronecker symbol. That is to say, primes p that are quadratic residues modulo 13.
Primes p such that p^6 == 1 (mod 13).
Primes p == 1, 3, 4, 9, 10, 12 (mod 13). (End)

Crossrefs

Cf. A011583 (kronecker symbol modulo 13), A038883.
Rational primes that decompose in the quadratic field with discriminant D: A139513 (D=-20), A191019 (D=-19), A191018 (D=-15), A296920 (D=-11), A033200 (D=-8), A045386 (D=-7), A002144 (D=-4), A002476 (D=-3), A045468 (D=5), A001132 (D=8), A097933 (D=12), this sequence (D=13), A296938 (D=17).
Cf. A038884 (inert rational primes in the field Q(sqrt(13))).

Programs

Formula

Equals A038883 \ {13}. - Jianing Song, Apr 21 2022

A155488 Primes p with property that p^2 is of the form x^2 + 40y^2.

Original entry on oeis.org

7, 11, 13, 19, 23, 37, 41, 47, 53, 59, 89, 103, 127, 131, 139, 157, 167, 173, 179, 197, 211, 223, 241, 251, 263, 277, 281, 293, 317, 331, 367, 373, 379, 383, 397, 401, 409, 419, 449, 463, 487, 491, 499, 503, 521, 557, 569, 571, 601, 607, 613, 619, 641, 647
Offset: 1

Views

Author

Zak Seidov, Jan 23 2009

Keywords

Comments

All p^2 are congruent to {1, 9} (mod 40), as in A107145.
Rational primes that decompose in the field Q(sqrt(-10)). - N. J. A. Sloane, Dec 26 2017

Crossrefs

Cf. A107145 (Primes of the form x^2 + 40y^2).

Programs

A293859 Prime factors of numbers of the form k^2 + 10.

Original entry on oeis.org

2, 5, 7, 11, 13, 19, 23, 37, 41, 47, 53, 59, 89, 103, 127, 131, 139, 157, 167, 173, 179, 197, 211, 223, 241, 251, 263, 277, 281, 293, 317, 331, 367, 373, 379, 383, 397, 401, 409, 419, 449, 463, 487, 491, 499, 503, 521, 557, 569, 571, 601, 607, 613, 619, 641
Offset: 1

Views

Author

J. Lowell, Oct 17 2017

Keywords

Comments

Primes p such that Legendre(-10,p) = 0 or 1. - N. J. A. Sloane, Dec 26 2017
Question: Is there a comment of the form "a prime number is in this sequence if and only if it is congruent to (list of appropriate values) mod n" for this sequence?
From Robert Israel, Nov 19 2017: (Start)
Prime p > 5 is in the sequence iff -10 is a quadratic residue mod p.
Thus p is either in the intersection of A002144 and A038879 or in neither of them.
Primes == 1, 2, 5, 7, 9, 11, 13, 19, 23, or 37 (mod 40). (End)

Examples

			7 is in the sequence because 2^2 + 10 = 14 is 2 times 7.
19 is in the sequence because 3^2 + 10 = 19.
		

Crossrefs

Programs

  • Maple
    select(isprime, [seq(seq(i*40+j, j = [1, 2, 5, 7, 9, 11, 13, 19, 23, 37]), i=0..40)]); # Robert Israel, Nov 19 2017
    # Load the Maple program HH given in A296920. Then run HH(-10, 200); This produces A155488, A296925, A293859. - N. J. A. Sloane, Dec 26 2017
  • Mathematica
    Select[Prime@ Range@ 120, {} != FindInstance[# x == n^2 + 10 && n >= 0 && x > 0, {n, x}, Integers, 1] &] (* Giovanni Resta, Oct 19 2017 *)

Extensions

More terms from Giovanni Resta, Oct 19 2017

A296915 Primes that are not squares mod 163.

Original entry on oeis.org

2, 3, 5, 7, 11, 13, 17, 19, 23, 29, 31, 37, 59, 67, 73, 79, 89, 101, 103, 107, 109, 127, 137, 139, 149, 157, 181, 191, 193, 211, 229, 233, 239, 241, 257, 269, 271, 277, 283, 293, 311, 317, 331, 337, 349, 353, 389, 401, 431, 433, 443, 449, 463, 467, 479, 491, 509, 521, 541
Offset: 1

Views

Author

Ed Pegg Jr, Dec 22 2017

Keywords

Comments

Inert rational primes in Q(sqrt -163). (Note that 41 is not inert in this field, it decomposes - see A296921.)

References

  • Helmut Hasse, Number Theory, Grundlehren 229, Springer, 1980, page 498.

Programs

  • Maple
    Load the Maple program HH given in A296920. Then run HH(-163,200); - N. J. A. Sloane, Dec 26 2017
  • PARI
    lista(nn) = forprime(p=2, nn, if (!issquare(Mod(p, 163)), print1(p, ", "));); \\ Michel Marcus, Dec 24 2017

Extensions

Corrected by N. J. A. Sloane, Dec 25 2017 (including deletion of incorrect comments in CROSS-REFERENCES)

A296921 Rational primes that decompose in the field Q(sqrt(-163)).

Original entry on oeis.org

41, 43, 47, 53, 61, 71, 83, 97, 113, 131, 151, 167, 173, 179, 197, 199, 223, 227, 251, 263, 281, 307, 313, 347, 359, 367, 373, 379, 383, 397, 409, 419, 421, 439, 457, 461, 487, 499, 503, 523, 547, 563, 577, 593, 607, 641, 647, 653, 661, 673, 677, 691, 701, 709, 733, 739, 743, 773, 787, 797
Offset: 1

Views

Author

N. J. A. Sloane, Dec 25 2017

Keywords

Comments

From Jianing Song, Oct 13 2022: (Start)
Primes p such that kronecker(-163,p) = 1 (or equivalently, kronecker(p,163) = 1).
Primes p such that p^81 == 1 (mod 163). (End)

Crossrefs

A257362, the sequence of primes that do not remain inert in the field Q(sqrt(-163)), is essentially the same.
Cf. A296915 (rational primes that remain inert in the field Q(sqrt(-163))).

Programs

  • Maple
    Load the Maple program HH given in A296920. Then run HH(-163,200);
  • PARI
    isA296921(p) = isprime(p) && kronecker(p,163) == 1

A296922 Primes p such that Legendre(-5,p) = 0 or 1.

Original entry on oeis.org

3, 5, 7, 23, 29, 41, 43, 47, 61, 67, 83, 89, 101, 103, 107, 109, 127, 149, 163, 167, 181, 223, 227, 229, 241, 263, 269, 281, 283, 307, 347, 349, 367, 383, 389, 401, 409, 421, 443, 449, 461, 463, 467, 487, 503, 509, 521, 523, 541, 547, 563, 569, 587, 601, 607, 641, 643
Offset: 1

Views

Author

N. J. A. Sloane, Dec 25 2017

Keywords

Comments

Primes == 1, 3, 5, 7, or 9 (mod 20). Primes whose 10's digit is even. - Robert Israel, Dec 27 2017

Crossrefs

Programs

  • Maple
    Load the Maple program HH given in A296920. Then run HH(-5,200);
    select(isprime, {seq(seq(20*i+j,j=[1,3,5,7,9]),i=0..100)}); # Robert Israel, Dec 27 2017
  • Mathematica
    Select[Prime@ Range@ 120, MemberQ[{0, 1}, KroneckerSymbol[-5, #]] &] (* or *)
    Select[Prime@ Range@ 120, MemberQ[Range[1, 9, 2], Mod[#, 20]] &] (* Michael De Vlieger, Jan 02 2018 *)
  • PARI
    lista(nn) = forprime(p=2, nn, if (kronecker(-5,p) >= 0, print1(p, ", "))); \\ Michel Marcus, Dec 26 2017

Formula

a(n) = A240920(n+1) for n >= 1. - Georg Fischer, Oct 30 2018

A296923 Primes p such that Legendre(-5,p) = -1.

Original entry on oeis.org

2, 11, 13, 17, 19, 31, 37, 53, 59, 71, 73, 79, 97, 113, 131, 137, 139, 151, 157, 173, 179, 191, 193, 197, 199, 211, 233, 239, 251, 257, 271, 277, 293, 311, 313, 317, 331, 337, 353, 359, 373, 379, 397, 419, 431, 433, 439, 457, 479, 491, 499, 557, 571, 577, 593, 599, 613
Offset: 1

Views

Author

N. J. A. Sloane, Dec 25 2017

Keywords

Comments

Primes == 2, 11, 13, 17, or 19 (mod 20). - Robert Israel, Dec 27 2017

Crossrefs

Programs

  • Maple
    Load the Maple program HH given in A296920. Then run HH(-5,200);
    select(isprime, {seq(seq(20*i+j,j=[2,11,13,17,19]),i=0..100)}); # Robert Israel, Dec 27 2017
  • PARI
    lista(nn) = forprime(p=2, nn, if (kronecker(-5,p) == -1, print1(p, ", "))); \\ Michel Marcus, Dec 26 2017

A296929 Rational primes that decompose in the field Q(sqrt(-17)).

Original entry on oeis.org

3, 7, 11, 13, 23, 31, 53, 71, 79, 89, 101, 107, 131, 137, 139, 149, 157, 163, 167, 199, 211, 227, 229, 257, 281, 283, 293, 311, 347, 349, 353, 367, 373, 379, 389, 409, 419, 421, 431, 433, 439, 457, 461, 479, 487, 499, 503, 509, 547, 557, 569, 571, 577, 593, 607
Offset: 1

Views

Author

N. J. A. Sloane, Dec 26 2017

Keywords

Programs

Formula

Primes == {1, 3, 7, 9, 11, 13, 21, 23, 25, 27, 31, 33, 39, 49, 53, 63} (mod 68). - Travis Scott, Jan 05 2023

A296931 Primes p such that Legendre(-17,p) = 0 or 1.

Original entry on oeis.org

2, 3, 7, 11, 13, 17, 23, 31, 53, 71, 79, 89, 101, 107, 131, 137, 139, 149, 157, 163, 167, 199, 211, 227, 229, 257, 281, 283, 293, 311, 347, 349, 353, 367, 373, 379, 389, 409, 419, 421, 431, 433, 439, 457, 461, 479, 487, 499, 503, 509, 547, 557
Offset: 1

Views

Author

N. J. A. Sloane, Dec 26 2017

Keywords

Comments

Primes p such that p == 1, 2, 3, 7, 9, 11, 13, 17, 21, 23, 25, 27, 31, 33, 39, 49, 53, or 63 (mod 68). - Robert Israel, Dec 26 2017

Programs

  • Maple
    Load the Maple program HH given in A296920. Then run HH(-17, 200); This produces A296929, A296930, A296931.
    Alternative:
    select(p-> isprime(p) and numtheory:-legendre(-17,p)<>-1, [2,seq(i,i=3..1000)]); # Robert Israel, Dec 26 2017
Previous Showing 11-20 of 28 results. Next