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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A128352 Numbers k such that (17^k - 5^k)/12 is prime.

Original entry on oeis.org

5, 7, 17, 23, 43, 71, 239, 733, 1097
Offset: 1

Views

Author

Alexander Adamchuk, Feb 27 2007

Keywords

Comments

All terms are primes.
a(10) > 10^5. - Robert Price, Jun 11 2013

Crossrefs

Cf. A062572, A128344, A128345, A128346, A128347, A128348, A128349, A128350, A128351, A128353, A128354.
Cf. A004061, A082182, A121877, A059802.
Cf. A057171, A082387, A122853, A128335, A128336, A128337, A128338, A128339, A128340, A128341, A128342.

Programs

  • Mathematica
    k=17; Do[p=Prime[n]; f=(k^p-5^p)/(k-5); If[ PrimeQ[f], Print[p] ], {n,1,100}]
  • PARI
    is(n)=isprime((17^n-5^n)/12) \\ Charles R Greathouse IV, Feb 17 2017

A128353 Numbers k such that (18^k - 5^k)/13 is prime.

Original entry on oeis.org

2, 3, 19, 23, 31, 37, 251, 283, 977, 28687, 32993
Offset: 1

Views

Author

Alexander Adamchuk, Feb 27 2007

Keywords

Comments

All terms are primes.
a(12) > 10^5. - Robert Price, Aug 10 2013

Crossrefs

Cf. A062572, A128344, A128345, A128346, A128347, A128348, A128349, A128350, A128351, A128352, A128354.
Cf. A004061, A082182, A121877, A059802.
Cf. A057171, A082387, A122853, A128335, A128336, A128337, A128338, A128339, A128340, A128341, A128342.

Programs

  • Mathematica
    k=18; Do[p=Prime[n]; f=(k^p-5^p)/(k-5); If[ PrimeQ[f], Print[p] ], {n,1,100}]
  • PARI
    is(n)=isprime((18^n-5^n)/13) \\ Charles R Greathouse IV, Feb 17 2017

Extensions

a(10)-a(11) from Robert Price, Aug 10 2013

A128354 Numbers k such that (19^k - 5^k)/14 is prime.

Original entry on oeis.org

5, 17, 31, 59, 373, 643, 2843, 5209, 85009
Offset: 1

Views

Author

Alexander Adamchuk, Feb 27 2007

Keywords

Comments

All terms are primes.
a(10) > 10^5. - Robert Price, Jul 22 2013

Crossrefs

Cf. A062572, A128344, A128345, A128346, A128347, A128348, A128349, A128350, A128351, A128352, A128353.
Cf. A004061, A082182, A121877, A059802.
Cf. A057171, A082387, A122853, A128335, A128336, A128337, A128338, A128339, A128340, A128341, A128342.

Programs

  • Mathematica
    k=19; Do[p=Prime[n]; f=(k^p-5^p)/(k-5); If[ PrimeQ[f], Print[p] ], {n,1,100}]
  • PARI
    is(n)=isprime((19^n-5^n)/14) \\ Charles R Greathouse IV, Feb 17 2017

Extensions

a(7)-a(9) from Robert Price, Jul 22 2013

A128349 Numbers k such that (13^k - 5^k)/8 is prime.

Original entry on oeis.org

5, 19, 71, 197, 659, 22079, 61949
Offset: 1

Views

Author

Alexander Adamchuk, Feb 27 2007

Keywords

Comments

All terms are primes.
a(8) > 10^5. - Robert Price, Mar 05 2013

Crossrefs

Cf. A062572, A128344, A128345, A128346, A128347, A128348, A128350, A128351, A128352, A128353, A128354.
Cf. A004061, A082182, A121877, A059802.
Cf. A057171, A082387, A122853, A128335, A128336, A128337, A128338, A128339, A128340, A128341, A128342.

Programs

  • Mathematica
    k=13; Do[p=Prime[n]; f=(k^p-5^p)/(k-5); If[ PrimeQ[f], Print[p] ], {n,1,100}]
  • PARI
    is(n)=isprime((13^n-5^n)/8) \\ Charles R Greathouse IV, Feb 17 2017

Extensions

a(6)-a(7) from Robert Price, Mar 05 2013

A128350 Numbers k such that (14^k - 5^k)/9 is prime.

Original entry on oeis.org

2, 151, 673, 709, 2999, 17909, 77213
Offset: 1

Views

Author

Alexander Adamchuk, Feb 27 2007

Keywords

Comments

All terms are primes.
a(8) > 10^5. - Robert Price, Apr 23 2013

Crossrefs

Cf. A062572, A128344, A128345, A128346, A128347, A128348, A128349, A128351, A128352, A128353, A128354. Cf. A004061, A082182, A121877, A059802. Cf. A057171, A082387, A122853, A128335, A128336, A128337, A128338, A128339, A128340, A128341, A128342.

Programs

  • Mathematica
    k=14; Do[p=Prime[n]; f=(k^p-5^p)/(k-5); If[ PrimeQ[f], Print[p] ], {n,1,200}]
  • PARI
    is(n)=isprime((14^n-5^n)/9) \\ Charles R Greathouse IV, Feb 17 2017

Extensions

One more term from Herman Jamke (hermanjamke(AT)fastmail.fm), May 01 2008
a(6) and a(7) from Robert Price, Apr 23 2013

A128338 Numbers k such that (8^k + 5^k)/13 is prime.

Original entry on oeis.org

7, 19, 167, 173, 223, 281, 21647
Offset: 1

Views

Author

Alexander Adamchuk, Feb 27 2007

Keywords

Comments

All terms are primes.
a(8) > 10^5. - Robert Price, Jan 21 2013

Crossrefs

Cf. A057171, A082387, A122853, A128335, A128336, A128337, A128339, A128340, A128341, A128342, A128343. Cf. A004061, A082182, A121877, A059802. Cf. A062572, A128344, A128345, A128346, A128347, A128348, A128349, A128350, A128351, A128352, A128353, A128354.

Programs

  • Mathematica
    k=8; Do[p=Prime[n]; f=(k^p+5^p)/(k+5); If[ PrimeQ[f], Print[p] ], {n,1,100}]
  • PARI
    is(n)=isprime((8^n+5^n)/13) \\ Charles R Greathouse IV, Feb 17 2017

Extensions

a(7) from Robert Price, Jan 21 2013

A187819 Numbers k such that (9^k + 8^k)/17 is prime.

Original entry on oeis.org

3, 7, 13, 19, 307, 619, 2089, 7297, 75571, 76103, 98897
Offset: 1

Views

Author

Robert Price, Dec 26 2012

Keywords

Comments

All terms are prime.
a(12) > 10^5.

Crossrefs

Cf. A181141, A128339, A057175, A125956.

Programs

  • Mathematica
    Select[ Prime[ Range[1, 100000] ], PrimeQ[ (9^# + 8^#)/17 ]& ]
  • PARI
    is(n)=isprime((9^n+8^n)/17) \\ Charles R Greathouse IV, Feb 17 2017

A217095 Numbers n such that (10^n + 9^n)/19 is prime.

Original entry on oeis.org

7, 67, 73, 1091, 1483, 10937
Offset: 1

Views

Author

Robert Price, Feb 17 2013

Keywords

Comments

The numbers n themselves (7, 67, 73, ...) are also prime.
a(7) > 10^5.

Crossrefs

Cf. A057175, A125956, A128339, A181141, A187819.

Programs

  • Mathematica
    Select[ Prime[ Range[1, 100000] ], PrimeQ[ (10^# + 9^#)/19 ]& ]
  • PARI
    is(n)=isprime((10^n+9^n)/19) \\ Charles R Greathouse IV, Feb 17 2017

A128343 Numbers k such that (14^k + 5^k)/19 is prime.

Original entry on oeis.org

3, 7, 17, 79, 17477, 19319, 49549
Offset: 1

Views

Author

Alexander Adamchuk, Feb 27 2007

Keywords

Comments

All terms are primes.
a(8) > 10^5. - Robert Price, May 20 2013

Crossrefs

Cf. A057171, A082387, A122853, A128335, A128336, A128337, A128338, A128339, A128340, A128341, A128342.
Cf. A004061, A082182, A121877, A059802.
Cf. A062572, A128344, A128345, A128346, A128347, A128348, A128349, A128350, A128351, A128352, A128353, A128354.

Programs

  • Mathematica
    k=14; Do[p=Prime[n]; f=(k^p+5^p)/(k+5); If[ PrimeQ[f], Print[p] ], {n,1,100}]
  • PARI
    is(n)=isprime((14^n+5^n)/19) \\ Charles R Greathouse IV, Feb 17 2017

Extensions

a(5)-a(7) from Robert Price, May 20 2013

A211409 Numbers n such that (9^n + 4^n)/13 is prime.

Original entry on oeis.org

3, 5, 7, 11, 17, 19, 41, 53, 109, 167, 2207, 3623, 5059, 5471, 7949, 21211, 32993, 60251
Offset: 1

Views

Author

Robert Price, Feb 09 2013

Keywords

Comments

All terms are prime.
The next element, a(19), is greater than 10^5.

Crossrefs

cf. A181141, A128339, A057175, A125956, A187819.

Programs

  • Mathematica
    Select[ Prime[ Range[1, 100000] ], PrimeQ[ (9^# + 4^#)/13 ]& ]
  • PARI
    is(n)=ispseudoprime((9^n+4^n)/13) \\ Charles R Greathouse IV, Jun 13 2017
Previous Showing 11-20 of 21 results. Next

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