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 1-10 of 16 results. Next

A108506 Integers n such that 10^n-59 is prime.

Original entry on oeis.org

2, 3, 4, 8, 20, 38, 95, 248, 263, 303, 304, 410, 438, 548, 688, 1074, 1575, 8364, 9910, 15910, 37344
Offset: 1

Views

Author

Julien Peter Benney (jpbenney(AT)ftml.net), Jul 06 2005

Keywords

Comments

Certified primality of numbers corresponding to terms 410, 438, 548, 688, 1074 and 1575 with Primo. - Ryan Propper, Jul 08 2005
No other terms <40000.
See Kamada link - primecount.txt for terms, primesize.txt for discovery details including probable or proved primes - search on "99941".

Examples

			8 is a member because: n = 8 gives 10^8-59 = 100000000-59 = 99999941, which is prime.

Links

Crossrefs

Cf. A089675, A095714, A092767, A108327, A108328, A108329, A108330, A108331, A108332, A177418.

Extensions

a(18)-a(20) from Kamada data by Robert Price, Dec 10 2010
a(21) by Robert Price, Dec 16 2010
Edited by Ray Chandler, Dec 23 2010

A178429 Numbers n such that 10^n - 51 is prime.

Original entry on oeis.org

4, 48, 64, 313, 484, 642, 11950, 15845, 18580, 50929
Offset: 1

Views

Author

Robert Price, Dec 21 2010

Keywords

Examples

			10^4 - 51 = 9949 which is a prime number.

Links

Crossrefs

Cf. A108330, A108328.

Programs

  • Maple
    A178429:=n->`if`(isprime(10^n-51), n, NULL): seq(A178429(n), n=1..1000); # Wesley Ivan Hurt, Nov 26 2014
  • Mathematica
    m = 1000; For[n = 1, n < m, If[PrimeQ[10^n - 51], Print[n]]; n++ ]
  • PARI
    is(n)=ispseudoprime(10^n-51) \\ Charles R Greathouse IV, Jun 06 2017

Extensions

a(10) = 50929 found by Robert Price and added by Patrick De Geest, Nov 26 2014

A108493 Integers n such that 10^n-57 is prime.

Original entry on oeis.org

2, 7, 10, 11, 17, 19, 39, 49, 50, 61, 95, 106, 187, 196, 849, 889, 6436, 7370, 14446, 19647, 34399, 39922, 81297, 84305
Offset: 1

Views

Author

Julien Peter Benney (jpbenney(AT)ftml.net), Jul 06 2005

Keywords

Comments

Numbers corresponding to terms 849 and 889 are certified primes. (Primo 2.2.0 beta) - Ryan Propper, Jul 13 2005
No additional terms <100000.
See Kamada link - primecount.txt for terms, primesize.txt for discovery details including probable or proved primes - search on "99943".

Examples

			n = 7 is a member because: 10^7-57 = 10000000-57 = 9999943, which is prime.

Links

Crossrefs

Cf. A089675, A095714, A092767, A108327, A108328, A108329, A108330, A108331, A108332, A177417.

Extensions

a(17)-a(19) from Kamada data by Robert Price, Dec 10 2010
a(20) from Kamada data by Robert Price, Dec 14 2010
a(21)-a(22) from Robert Price, Dec 15 2010
Edited by Ray Chandler, Dec 23 2010
a(23-24)=81297,84305 from Robert Price, May 29 2011

A177866 Numbers n such that 10^n - 69 is prime.

Original entry on oeis.org

2, 4, 6, 7, 8, 14, 20, 110, 138, 140, 145, 300, 390, 1484, 3194, 3300, 3950, 4986, 5574, 5630, 5874, 8866, 11390, 45130, 86110
Offset: 1

Views

Author

Robert Price, Dec 28 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 "99931".

Examples

			10^6 - 69 = 999931 which is a prime number.

Links

Crossrefs

Cf. A108330, A108328.

Programs

Extensions

a(24-25)=45130,86110 from Robert Price, May 29 2011

A108364 Integers k such that 10^k - 33 is prime.

Original entry on oeis.org

2, 3, 4, 10, 18, 46, 48, 121, 154, 158, 170, 196, 211, 250, 294, 316, 320, 663, 975, 1165, 1351, 4126, 4270, 5724, 7156, 15025, 19132, 25035, 36174, 77418
Offset: 1

Views

Author

Parthasarathy Nambi, Jul 01 2005

Keywords

Comments

See Kamada link - primecount.txt for terms, primesize.txt for discovery details including probable or proved primes - search on "99967".
The next term, if one exists, is > 100000. - Robert Price, Apr 25 2011

Examples

			k=2 is a term because 10^2 - 33 = 67 (prime).
k=48 is a term because 10^48 - 33 = 999999999999999999999999999999999999999999999967 (prime).

Links

Crossrefs

Cf. A108330, A108328.

Programs

  • Mathematica
    For[n = 1, n < 1000, n++, If[PrimeQ[10^n - 33], Print[n]]] (Steinerberger)

Extensions

a(8)-a(21) from Stefan Steinerberger, Jan 28 2006
a(22)-a(29) extracted from Makoto Kamada website by Robert Price, Dec 06 2010
Edited by Ray Chandler, Dec 23 2010
a(30) from Robert Price, Apr 25 2011

A108365 Integers k such that 10^k - 39 is prime.

Original entry on oeis.org

2, 5, 6, 12, 17, 19, 61, 102, 195, 447, 1250, 1329, 1935, 3930, 5837, 7176, 8724, 20881, 23936, 61868, 91920
Offset: 1

Views

Author

Parthasarathy Nambi, Jul 01 2005

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 "99961".

Examples

			k=2 is a term because 10^2 - 39 = 61 (prime).
k=61 is a term because 10^61 - 39 = 9999999999999999999999999999999999999999999999999999999999961 (prime).

Links

Crossrefs

Cf. A108330, A108328.

Extensions

a(8)-a(12) from Stefan Steinerberger, Nov 05 2005
a(13)-a(19) from Robert Price, Dec 12 2010
Edited by Ray Chandler, Dec 23 2010
a(20)-a(21) from Robert Price, Apr 25 2011

A178175 Numbers n such that 10^n - 47 is prime.

Original entry on oeis.org

2, 3, 6, 33, 48, 74, 231, 3206, 4544, 7064, 13634, 41384, 64862, 82790
Offset: 1

Views

Author

Robert Price, Dec 17 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 "99953".

Examples

			10^3 - 47 = 953 is a prime number.

Links

Crossrefs

Cf. A108330, A108328.

Programs

Extensions

a(12:14)=41384,64862,82790 from Robert Price, Apr 25 2011

A178406 Numbers n such that 10^n - 41 is prime.

Original entry on oeis.org

2, 6, 8, 12, 14, 47, 88, 130, 414, 1388, 1932, 4106, 4412, 12870, 22956, 23932, 27312, 35316, 37169, 43873, 150029
Offset: 1

Views

Author

Robert Price, Dec 21 2010

Keywords

Comments

The next term, if one exists, is >100000. - Robert Price, Apr 25 2011
a(22) > 2.5*10^5. - Robert Price, Apr 12 2015

Examples

			10^6 - 41 = 999959 which is a prime number.

Links

Crossrefs

Cf. A108330, A108328.

Programs

Extensions

a(20)=43873 from Robert Price, Apr 25 2011
a(21) from Kamada data by Robert Price, Apr 12 2015

A178430 Numbers n such that 10^n - 53 is prime.

Original entry on oeis.org

2, 3, 11, 15, 23, 29, 44, 71, 83, 95, 159, 383, 404, 548, 633, 6409, 8793, 24146, 25727, 64436, 74335, 76875
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 "99947".

Examples

			10^3 - 53 = 947 which is a prime number.

Links

Crossrefs

Cf. A108330, A108328.

Programs

Extensions

Corrected terms a(17) and a(18) by Robert Price, Dec 24 2010
a(20-22)=64436,74335,76875 from Robert Price, May 29 2011

A178433 Numbers n such that 10^n - 63 is prime.

Original entry on oeis.org

2, 3, 7, 9, 12, 16, 33, 78, 124, 334, 3618, 3682, 3739, 4732, 6676, 16014, 20023, 20364, 66793
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 "99937".

Examples

			10^3 - 63 = 937 which is a prime number.

Links

Crossrefs

Cf. A108330, A108328.

Programs

  • Mathematica
    nMax=1000; Do[If[PrimeQ[10^n-63], Print[n]], {n, nMax}]
  • PARI
    is(n)=ispseudoprime(10^n-63) \\ Charles R Greathouse IV, Jun 13 2017

Extensions

a(19)=66793 from Robert Price, May 29 2011
Showing 1-10 of 16 results. Next

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