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.

Showing 1-4 of 4 results.

A014754 Primes p == 1 mod 8 such that 2 and -2 are both 4th powers (one implies other) mod p.

Original entry on oeis.org

73, 89, 113, 233, 257, 281, 337, 353, 577, 593, 601, 617, 881, 937, 1033, 1049, 1097, 1153, 1193, 1201, 1217, 1249, 1289, 1433, 1481, 1553, 1601, 1609, 1721, 1753, 1777, 1801, 1889, 1913, 2089, 2113, 2129, 2273, 2281, 2393, 2441, 2473, 2593, 2657, 2689
Offset: 1

Views

Author

Warren D. Smith

Keywords

Comments

Primes p such that x^4 == 2 has more than two (in fact four) solutions mod p. This is the sequence of terms common to A040098 (primes p such that x^4 == 2 has a solution mod p) and A007519 (primes of form 8n+1). Solutions mod p are represented by integers from 0 to p - 1. For p > 2, i is a solution mod p of x^4 == 2 iff p - i is a solution mod p of x^4 == 2, thus the sum of first and fourth solution is p and so is the sum of second and third solution. The solutions are given in A065909, A065910, A065911 and A065912. - Klaus Brockhaus, Nov 28 2001
Primes of the form x^2+64y^2. - T. D. Noe, May 13 2005

Links

Crossrefs

Cf. A040098, A007519, A014754, A007522, A065909, A065910, A065911, A065912, A070179.

Programs

  • PARI
    A014754(m) = local(p,s,x,z); forprime(p = 3,m,s = []; for(x = 0,p-1, if(x^4%p == 2%p,s = concat(s,[x]))); z = matsize(s)[2]; if(z>2,print1(p,",")))
  • PARI
    {a(n) = local(m, c, x); if( n<1, 0, c = 0; m = 1; while( cMichael Somos, Mar 22 2008 */
  • PARI
    forprime(p=1, 9999, p%8==1&&ispower(Mod(2, p), 4)&&print1(p", ")) \\ M. F. Hasler, Feb 18 2014
  • PARI
    is_A014754(p)={p%8==1&&ispower(Mod(2, p), 4)&&isprime(p)} \\ M. F. Hasler, Feb 18 2014

Extensions

Removed erroneous Mma program; extended b-file using first PARI program of M. F. Hasler. - N. J. A. Sloane, Jun 06 2014

A065909 First solution mod p of x^4 = 2 for primes p such that more than two solutions exist.

Original entry on oeis.org

18, 5, 27, 28, 35, 46, 131, 48, 252, 104, 45, 123, 51, 9, 69, 77, 51, 177, 472, 261, 55, 117, 224, 562, 12, 264, 273, 132, 127, 500, 17, 197, 107, 36, 206, 671, 127, 159, 137, 684, 329, 564, 316, 314, 197, 98, 661, 925, 461, 170, 930, 151, 1081, 333, 434, 924
Offset: 1

Views

Author

Klaus Brockhaus, Nov 29 2001

Keywords

Comments

Conjecture: no integer occurs more than three time in this sequence. Confirmed for the first 1182 terms of A014754 (primes < 100000). There are integers which do occur thrice, e.g. 6624. Moreover, no integer is first, second, third or fourth solution for more than three primes. Confirmed for the first 2399 terms of A007522 and the first 1182 terms of A014754 (primes < 100000).

Examples

			a(3) = 27, since 113 is the third term of A014754, 27, 47, 66 and 86 are the solutions mod 113 of x^4 = 2 and 27 is the least one.

Crossrefs

Cf. A040098, A007522, A014754, A065910, A065911, A065912.

Programs

  • PARI
    a065909(m) = local(s); forprime(p = 2,m,s = []; for(x = 0,p-1, if(x^4%p == 2%p,s = concat(s,[x]))); if(matsize(s)[2]>2,print1(s[1],",")))
a065909(4000)

Formula

a(n) = first (least) solution mod p of x^4 = 2, where p is the n-th prime such that x^4 = 2 has more than two solutions mod p, i.e. p is the n-th term of A014754.

Extensions

Definition corrected by Harvey P. Dale, Apr 16 2015

A065911 Third solution mod p of x^4 = 2 for primes p such that more than two solution exists.

Original entry on oeis.org

48, 81, 66, 162, 211, 190, 179, 251, 299, 299, 385, 416, 526, 827, 736, 766, 936, 586, 703, 779, 639, 999, 980, 808, 1137, 975, 1314, 1458, 1557, 1112, 1041, 1563, 1415, 1150, 1681, 1355, 1723, 1623, 1468, 1303, 1398, 1702, 2265, 1958, 1787, 2668, 2000
Offset: 1

Views

Author

Klaus Brockhaus, Nov 29 2001

Keywords

Comments

Conjecture: no integer occurs more than three time in this sequence. Confirmed for the first 1182 terms of A014754 (primes < 100000). In this section, there are no integers which do occur thrice. Moreover, no integer is first, second, third or fourth solution for more than three primes. Confirmed for the first 2399 terms of A007522 and the first 1182 terms of A014754 (primes < 100000).

Examples

			a(3) = 66, since 113 is the third term of A014754, 27, 47, 66 and 86 are the solutions mod 113 of x^4 = 2 and 66 is the third one.

Crossrefs

Cf. A040098, A007522, A014754, A065909, A065910, A065912.

Programs

  • PARI
    a065911(m) = local(s); forprime(p = 2,m,s = []; for(x = 0,p-1, if(x^4%p == 2%p,s = concat(s,[x]))); if(matsize(s)[2]>2,print1(s[3],",")))
a065911(3000)

Formula

a(n) = third solution mod p of x^4 = 2, where p is the n-th prime such that x^4 = 2 has more than two solutions mod p, i.e. p is the n-th term of A014754.

A065912 Fourth solution mod p of x^4 = 2 for primes p such that more than two solution exists.

Original entry on oeis.org

55, 84, 86, 205, 222, 235, 206, 305, 325, 489, 556, 494, 830, 928, 964, 972, 1046, 976, 721, 940, 1162, 1132, 1065, 871, 1469, 1289, 1328, 1477, 1594, 1253, 1760, 1604, 1782, 1877, 1883, 1442, 2002, 2114, 2144, 1709, 2112, 1909, 2277, 2343, 2492, 2735
Offset: 1

Views

Author

Klaus Brockhaus, Nov 29 2001

Keywords

Comments

Conjecture: no integer occurs more than three time in this sequence. Confirmed for the first 1182 terms of A014754 (primes < 100000). In this section, there are no integers which do occur thrice. Moreover, no integer is first, second, third or fourth solution for more than three primes. Confirmed for the first 2399 terms of A007522 and the first 1182 terms of A014754 (primes < 100000).

Examples

			a(3) = 86, since 113 is the third term of A014754, 27, 47, 66 and 86 are the solutions mod 113 of x^4 = 2 and 86 is the fourth one.

Crossrefs

Cf. A040098, A007522, A014754, A065909, A065910, A065911.

Programs

  • PARI
    a065912(m) = local(s); forprime(p = 2,m,s = []; for(x = 0,p-1, if(x^4%p == 2%p,s = concat(s,[x]))); if(matsize(s)[2]>3,print1(s[4],",")))
a065912(3000)

Formula

a(n) = fourth solution mod p of x^4 = 2, where p is the n-th prime such that x^4 = 2 has more than two solutions mod p, i.e. p is the n-th term of A014754.
Showing 1-4 of 4 results.

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