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.

A178434 Numbers n such that 10^n - 71 is prime.

Original entry on oeis.org

2, 3, 4, 5, 7, 9, 10, 14, 22, 98, 127, 151, 158, 274, 377, 1015, 2146, 8499, 13885, 13991, 17834, 18211, 36271, 52317, 53804, 104212, 117059, 178695
Offset: 1

Views

Author

Robert Price, Dec 21 2010

Keywords

Comments

a(29) > 2.5*10^5. - Robert Price, Apr 12 2015

Examples

			10^4 - 71 = 9929 which is a prime number.

Links

Crossrefs

Cf. A108330, A108328.

Programs

  • Mathematica
    nMax=1000; Do[If[PrimeQ[10^n-71], Print[n]], {n, nMax}]
  • PARI
    is(n)=ispseudoprime(10^n-71) \\ Charles R Greathouse IV, Jun 13 2017

Extensions

a(24:25)=52317,53804 from Robert Price, Apr 25 2011
a(26)-a(28) from Kamada data by Robert Price, Apr 12 2015

A178436 Numbers n such that 10^n - 77 is prime.

Original entry on oeis.org

2, 4, 5, 14, 44, 64, 103, 282, 643, 670, 818, 1092, 1775, 1856, 4080, 4178, 4498, 6815, 8293, 10112, 12023, 13643
Offset: 1

Views

Author

Robert Price, Dec 21 2010

Keywords

Comments

The next term, if one exists, is >100000. - Robert Price, Apr 25 2011
See Kamada link - primecount.txt for terms, primesize.txt for discovery details including probable or proved primes - search on "99923".

Examples

			10^4 - 77 = 9923 which is a prime number.

Links

Crossrefs

Cf. A108330, A108328.

Programs

  • Mathematica
    nMax=1000; Do[If[PrimeQ[10^n-77], Print[n]], {n, nMax}]
  • PARI
    is(n)=ispseudoprime(10^n-77) \\ Charles R Greathouse IV, Jun 13 2017

A178437 Numbers n such that 10^n - 81 is prime.

Original entry on oeis.org

2, 3, 17, 19, 31, 37, 43, 91, 339, 367, 407, 1135, 1175, 8653, 11987, 15793
Offset: 1

Views

Author

Robert Price, Dec 21 2010

Keywords

Comments

The next term, if one exists, is >100000. - Robert Price, Apr 25 2011

Examples

			10^3 - 81 = 919 which is a prime number.

Links

Crossrefs

Cf. A108330, A108328.

Programs

  • Mathematica
    nMax=1000; Do[If[PrimeQ[10^n-81], Print[n]], {n, nMax}]
  • PARI
    is(n)=ispseudoprime(10^n-81) \\ Charles R Greathouse IV, Jun 13 2017

A178438 Numbers n such that 10^n - 83 is prime.

Original entry on oeis.org

2, 6, 16, 42, 47, 62, 109, 191, 221, 509, 3671, 4229, 4886, 6967, 12086
Offset: 1

Views

Author

Robert Price, Dec 21 2010

Keywords

Comments

The next term, if one exists, is > 100000. - Robert Price, Apr 25 2011
See Kamada link - primecount.txt for terms, primesize.txt for discovery details including probable or proved primes - search on "99917".

Examples

			10^6 - 83 = 999917 which is a prime number.

Links

Crossrefs

Cf. A108330, A108328.

Programs

  • Mathematica
    nMax=1000; Do[If[PrimeQ[10^n-83], Print[n]], {n, nMax}]
  • PARI
    is(n)=ispseudoprime(10^n-83) \\ Charles R Greathouse IV, Jun 13 2017

Extensions

Example corrected by Patrick De Geest, Nov 28 2014

A178439 Numbers n such that 10^n - 99 is prime.

Original entry on oeis.org

4, 5, 7, 27, 91, 248, 347, 501, 535, 767, 2002, 2581, 2677, 8158, 15977, 20666, 23854, 72730, 86816
Offset: 1

Views

Author

Robert Price, Dec 21 2010

Keywords

Comments

The next term, if it exists, is > 100000.
See Kamada link - primecount.txt for terms, primesize.txt for discovery details including probable or proved primes - search on "99901".

Examples

			10^4 - 99 = 9901 which is a prime number.

Links

Crossrefs

Cf. A108330, A108328.

Programs

  • Mathematica
    nMax=1000; Do[If[PrimeQ[10^n-99], Print[n]], {n, nMax}]
  • PARI
    is(n)=ispseudoprime(10^n-99) \\ Charles R Greathouse IV, Jun 13 2017

Extensions

a(18-19)=72730,86816 from Robert Price, May 29 2011

A178531 Numbers n such that 10^n - 93 is prime.

Original entry on oeis.org

2, 3, 4, 5, 6, 7, 11, 57, 61, 70, 127, 223, 237, 240, 310, 467, 651, 1935, 2333, 3457, 4456, 6048, 11289, 12150, 24693, 28437, 31123, 32909, 52041, 58225, 68297, 201801
Offset: 1

Views

Author

Robert Price, Dec 23 2010

Keywords

Comments

a(33) > 3*10^5.
See Kamada link - primecount.txt for terms, primesize.txt for discovery details including probable or proved primes - search on "99907" or "9w07".

Examples

			10^3 - 93 = 907 which is a prime number.

Links

Crossrefs

Cf. A108330, A108328.

Programs

Extensions

a(29-31) from Robert Price, May 29 2011
a(32) from Robert Price, Jun 21 2023
Previous Showing 11-16 of 16 results.

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