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 1-5 of 5 results.

A367102 Numbers k such that k^4*2^k - 1 is a prime.

Original entry on oeis.org

3, 29, 43, 83, 133, 209, 271, 329, 415, 727, 2437, 5673, 6879, 7813, 8125, 11931, 29433, 29491, 38397, 91141, 99459, 110935, 127247
Offset: 1

Views

Author

Juri-Stepan Gerasimov, Nov 04 2023

Keywords

Crossrefs

Numbers k such that k^m*2^k - 1 is prime: A000043 (m = 0), A002234 (m = 1), A058781 (m = 2), A367037 (m = 3), this sequence (m = 4).

Programs

  • Magma
    [k: k in [1..500] | IsPrime(k^4*2^k-1)];
  • Mathematica
    Select[Range[6000], PrimeQ[#^4*2^# - 1] &] (* Amiram Eldar, Nov 05 2023 *)

Extensions

a(17)-a(18) from Amiram Eldar, Nov 05 2023
a(19) from Michael S. Branicky, Nov 05 2023
a(20)-a(23) from Hugo Pfoertner, Nov 08 2023, Nov 10 2023

A367464 Numbers k such that k^5*2^k - 1 is a prime.

Original entry on oeis.org

2, 6, 9, 18, 42, 132, 139, 482, 523, 524, 859, 909, 948, 979, 1158, 1741, 2364, 3519, 4388, 5952, 6266, 8564, 12169, 14448, 54944, 103526, 116563, 125918
Offset: 1

Views

Author

Juri-Stepan Gerasimov, Nov 18 2023

Keywords

Crossrefs

Numbers k such that k^m*2^k - 1 is a prime: A000043 (m = 0), A002234 (m = 1), A058781 (m = 2), A367037 (m = 3), A367102 (m = 4), this sequence (m = 5).
Cf. A367421.

Programs

  • Magma
    [k: k in [1..1000] | IsPrime(k^5*2^k-1)];
  • Mathematica
    Select[Range[2500], PrimeQ[#^5*2^# - 1] &] (* Amiram Eldar, Nov 19 2023 *)

Extensions

a(24)-a(25) from Michael S. Branicky, Nov 18 2023
a(26)-a(28) from Michael S. Branicky, Aug 26 2024

A367478 Numbers k such that k^6*2^k - 1 is a prime.

Original entry on oeis.org

37, 43, 167, 217, 239, 349, 581, 1297, 5183, 9119, 10589, 15205, 18745, 25687, 26609, 33667, 35663, 73603, 82501, 89269
Offset: 1

Views

Author

Juri-Stepan Gerasimov, Nov 19 2023

Keywords

Crossrefs

Numbers k such that k^m*2^k - 1 is a prime: A000043 (m = 0), A002234 (m = 1), A058781 (m = 2), A367037 (m = 3), A367102 (m = 4), A367464 (m = 5), this sequence (m = 6).

Programs

  • Magma
    [k: k in [1..1000] | IsPrime(k^6*2^k-1)];
  • Mathematica
    Select[Range[6000], PrimeQ[#^6*2^# - 1] &] (* Amiram Eldar, Nov 19 2023 *)

Extensions

a(12) inserted by and a(14)-a(17) from Michael S. Branicky, Nov 19 2023
a(18)-a(20) from Michael S. Branicky, Nov 21 2023

A367561 Numbers k such that k^7*2^k - 1 is a prime.

Original entry on oeis.org

6, 45, 55, 80, 135, 187, 205, 384, 405, 1291, 1364, 2301, 2486, 2844, 16892, 27308, 30152, 32535, 45324, 71522, 72865
Offset: 1

Views

Author

Juri-Stepan Gerasimov, Nov 22 2023

Keywords

Comments

No further terms <= 100000. - Michael S. Branicky, Aug 28 2024

Crossrefs

Numbers k such that k^m*2^k - 1 is a prime: A000043 (m = 0), A002234 (m = 1), A058781 (m = 2), A367037 (m = 3), A367102 (m = 4), A367464 (m = 5), A367478 (m = 6), this sequence (m = 7).
Cf. A367560.

Programs

  • Magma
    [k: k in [1..4000] | IsPrime(k^7*2^k-1)];
  • Mathematica
    Select[Range[3000], PrimeQ[#^7*2^# - 1] &] (* Amiram Eldar, Nov 23 2023 *)

Extensions

a(16)-a(21) from Michael S. Branicky, Nov 23 2023

A367572 Numbers k such that k^8*2^k - 1 is a prime.

Original entry on oeis.org

5, 7, 49, 165, 251, 345, 385, 945, 949, 1001, 1963, 2113, 2249, 3751, 4381, 4911, 5133, 10039, 29693, 34901, 73885, 99319, 104883, 113613
Offset: 1

Views

Author

Juri-Stepan Gerasimov, Nov 23 2023

Keywords

Crossrefs

Numbers k such that k^m*2^k - 1 is a prime: A000043 (m = 0), A002234 (m = 1), A058781 (m = 2), A367037 (m = 3), A367102 (m = 4), A367464 (m = 5), A367478 (m = 6), A367561 (m = 7), this sequence (m = 8).

Programs

  • Magma
    [k: k in [1..4000] | IsPrime(k^8*2^k-1)];
  • Mathematica
    Select[Range[5000], PrimeQ[#^8*2^# - 1] &] (* Amiram Eldar, Nov 23 2023 *)

Extensions

a(19)-a(20) from Michael S. Branicky, Nov 23 2023
a(21) from Michael S. Branicky, Nov 25 2023
a(22)-a(24) from Michael S. Branicky, Aug 29 2024
Showing 1-5 of 5 results.

Started in 1964 by Neil J. A. Sloane | Maintained by The OEIS Foundation Inc.

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