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.

Previous Showing 11-16 of 16 results.

A274235 Numbers n such that n^2048 + (n+1)^2048 is prime.

Original entry on oeis.org

754, 1289, 1368, 1813, 3159, 3280, 3301, 4976, 6204, 6283, 6723, 6904, 7141, 10246, 11417, 13268, 15456, 19428, 19683, 19698, 20298, 21484, 22543, 23702, 23815, 24747, 27010, 32319, 34133, 36201, 37030, 39438, 41292, 44472, 47623, 50198, 51031, 51370, 51521, 52628, 53073, 53309, 53767, 55911, 56630, 59424
Offset: 1

Views

Author

Tim Johannes Ohrtmann, Jun 15 2016

Keywords

Comments

The terms correspond only to probable primes.

Crossrefs

Programs

  • Magma
    [n: n in [1..10000] |IsPrime(n^2048 + (n+1)^2048)];
  • Mathematica
    Select[Range[1, 10000], PrimeQ[#^2048 + (#+1)^2048] &]
  • PARI
    for(n=1, 10000, if(isprime(n^2048 + (n+1)^2048), print1(n, ", ")))
    

A274236 Numbers k such that k^4096 + (k+1)^4096 is prime.

Original entry on oeis.org

311, 2741, 3582, 5293, 6289, 12080, 14082, 16886, 17971, 19936, 21454, 21486, 26652, 26904, 28314, 34693, 35778, 36292, 40868, 43819, 46356, 46467, 49653, 53996, 57150, 58169, 64937, 67398, 77383, 82577, 86031, 86102, 87352, 87684, 89030, 93340, 95346, 97320, 98191, 111483, 113947, 118052, 125442, 125836, 126157, 127832, 130794
Offset: 1

Views

Author

Tim Johannes Ohrtmann, Jun 15 2016

Keywords

Comments

The terms correspond only to probable primes.

Crossrefs

Programs

  • Magma
    [n: n in [1..10000] |IsPrime(n^4096 + (n+1)^4096)];
  • Mathematica
    Select[Range[1, 10000], PrimeQ[#^4096 + (#+1)^4096] &]
  • PARI
    for(n=1, 10000, if(isprime(n^4096 + (n+1)^4096), print1(n, ", ")))
    

A274237 Numbers k such that k^8192 + (k+1)^8192 is prime.

Original entry on oeis.org

3508, 5209, 13428, 15347, 16339, 17779, 22548, 37726, 40408
Offset: 1

Views

Author

Tim Johannes Ohrtmann, Jun 15 2016

Keywords

Comments

The terms correspond only to probable primes.

Crossrefs

Programs

  • Magma
    [n: n in [1..10000] |IsPrime(n^8192 + (n+1)^8192)]
  • Mathematica
    Select[Range[1, 10000], PrimeQ[#^8192 + (#+1)^8192] &]
  • PARI
    for(n=1, 10000, if(isprime(n^8192 + (n+1)^8192), print1(n, ", ")))
    

A122902 First occurrence of exponent n in A080121 corresponding to the minimum prime of the form (k^(2^n) + (k+1)^(2^n)) = A122900(k).

Original entry on oeis.org

1, 3, 23, 21, 10, 95, 255, 86, 59
Offset: 1

Views

Author

Alexander Adamchuk, Sep 18 2006, Oct 01 2006

Keywords

Comments

Minimum primes of the form n^(2^m) + (n+1)^(2^m) are listed in A122900. The exponents m are listed in A080121.
a(10)-a(13)>1000, a(14)-a(16)>100.

Examples

			A080121 begins with 1,1,2,1,1,2,1,2,1,5,?,1,2,1,?,2,1,?,1,?,4,1,3,1,..., where the unknown terms (denoted with ?) are at least 10. So a(1) = 1, a(2) = 3, a(3) = 23, a(4) = 21, a(5) = 10.
		

Crossrefs

Extensions

Edited by Max Alekseyev, Sep 09 2020

A168149 Numbers n such that n^8+(n-1)^8 is a prime.

Original entry on oeis.org

2, 6, 18, 24, 33, 34, 36, 40, 43, 67, 69, 77, 79, 91, 114, 119, 130, 153, 182, 187, 189, 199, 221, 222, 230, 232, 288, 301, 307, 308, 312, 317, 349, 363, 381, 402, 410, 415, 427, 444, 454, 465, 488, 504, 509, 511, 512, 561, 573, 594, 629, 645, 647, 663, 692
Offset: 1

Views

Author

Vincenzo Librandi, Nov 19 2009

Keywords

Crossrefs

Cf. A153504.

Programs

  • Magma
    [n: n in [0..700] | IsPrime(n^8 + (n-1)^8)]; // Vincenzo Librandi, Apr 05 2013
  • Mathematica
    Select[Range[0, 1000], PrimeQ[#^8 + (#-1)^8]&] (* Vincenzo Librandi, Apr 05 2013 *)

Extensions

308 and 512 inserted by R. J. Mathar, Nov 19 2009

A244932 Least number k > n such that k^8 + n^8 is prime.

Original entry on oeis.org

2, 13, 10, 17, 6, 37, 12, 13, 16, 27, 24, 71, 16, 31, 64, 43, 18, 43, 26, 23, 32, 29, 24, 79, 32, 53, 34, 61, 92, 47, 40, 33, 34, 57, 36, 47, 40, 53, 40, 79, 44, 43, 68, 91, 68, 57, 66, 61, 60, 53, 58, 83, 60, 91, 94, 61, 82, 61, 70, 101, 82, 71, 68, 145, 82, 67, 76, 69, 100
Offset: 1

Views

Author

Derek Orr, Jul 08 2014

Keywords

Comments

a(n) = n+1 iff n is in A153504.

Examples

			13^8 + 14^8 = 2291519777 is not prime, 13^8 + 15^8 = 3378621346 is not prime. 13^8 + 16^8 = 5110698017 is prime. Thus a(13) = 16.
		

Crossrefs

Programs

  • PARI
    a(n)=for(k=n+1,10^4,if(isprime(k^8+n^8),return(k)))
    n=1;while(n<100,print1(a(n),", ");n++)
  • Python
    import sympy
    from sympy import isprime
    def a(n):
      for k in range(n+1,10**4):
        if isprime(k**8+n**8):
          return k
    n = 1
    while n < 100:
      print(a(n),end=', ')
      n += 1
    
Previous Showing 11-16 of 16 results.