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 30 results. Next

A108052 Integers k such that 10^k+19 is a prime number.

Original entry on oeis.org

1, 3, 5, 7, 10, 11, 17, 59, 81, 108, 574, 629, 1069, 1759, 2063, 2682, 9174, 40929, 42457, 66033
Offset: 1

Views

Author

Julien Peter Benney (jpbenney(AT)ftml.net), Jun 01 2005

Keywords

Comments

Verified terms through 9174. - Robert Price, May 24 2010
See Kamada link - primecount.txt for terms, primesize.txt for discovery details including probable or proved primes - search on "10019".
No other terms <= 100,000. - Robert Price, Mar 03 2011

Examples

			n = 7 we have 10^7+19 = 10000000+19 = 10000019, which is prime.

Links

Crossrefs

Cf. A049054, A088274, A088275, A095688.

Programs

Extensions

a(17)=9174 from Ryan Propper, Jan 02 2008
Edited by Ray Chandler, Dec 23 2010
a(18)=40929 and a(19)=42457 from Robert Price, Dec 27 2010
a(20)=66033 from Robert Price, Jan 09 2011

A108054 Integers k such that 10^k+49 is prime.

Original entry on oeis.org

1, 2, 3, 5, 8, 17, 24, 32, 65, 66, 67, 79, 83, 98, 152, 260, 781, 1225, 1777, 2023, 2411, 3469, 5347, 10646, 11335, 13989, 14792, 16731, 19015, 29471, 39187, 41456, 80883, 102824, 154359, 216950, 294475
Offset: 1

Views

Author

Julien Peter Benney (jpbenney(AT)ftml.net), Jun 02 2005

Keywords

Comments

See Kamada link - primecount.txt for terms, primesize.txt for discovery details including probable or proved primes - search on "10049".
a(38) > 3*10^5. Robert Price, Jul 10 2023

Examples

			k = 8 ==> 10^8+49 = 100000049, which is prime.

Links

Crossrefs

Cf. A049054, A088274, A088275, A095688.

Programs

Extensions

a(23) from Ray G. Opao, Dec 13 2006
a(24)-a(31) from Robert Price, May 28 2010
Edited by Ray Chandler, Dec 23 2010
a(32) from Robert Price, Dec 27 2010
a(33) from Robert Price, Mar 03 2011
a(34)-a(37) from Robert Price, Jul 10 2023

A107083 Integers k such that 10^k + 31 is prime.

Original entry on oeis.org

1, 2, 3, 14, 18, 44, 54, 89, 469, 2060, 2985, 6197, 16452, 19393, 21205, 49657, 74670, 76374
Offset: 1

Views

Author

Julien Peter Benney (jpbenney(AT)ftml.net), Jun 08 2005

Keywords

Comments

The next term, if one exists, is >100000. - Robert Price, Apr 26 2011
See Kamada link - primecount.txt for terms, primesize.txt for discovery details including proofs of primality - search on "10031".

Examples

			For k = 3 we get 10^3 + 31 = 1000 + 31 = 1031, which is prime.

Links

Crossrefs

Cf. A049054, A088274, A088275, A095688, A108052, A108050, A108049, A108054.

Programs

Extensions

16452 and 19393 from Robert Price, Mar 22 2010
Additional term (21205) from Robert Price, May 24 2010
Missing term (6197) added by Robert Price, Dec 07 2010
Edited by Ray Chandler, Dec 23 2010
a(16)=49657 from Robert Price, Dec 31 2010
a(17)=74670 from Robert Price, Jan 29 2011
a(18)=76374 from Robert Price, Mar 03 2011

A108312 Integers n such that 10^n + 27 is prime.

Original entry on oeis.org

1, 2, 83, 167, 242, 14081, 65537
Offset: 1

Views

Author

Julien Peter Benney (jpbenney(AT)ftml.net), Jun 29 2005

Keywords

Comments

The next term, if one exists, is >100000. - Robert Price, May 24 2010
See Kamada link - primecount.txt for terms, primesize.txt for discovery details including probable or proved primes - search on "10027".

Examples

			For n=2 we have 10^2 + 27 = 100 + 27 = 127, which is prime.

Links

Crossrefs

Cf. A049054, A088274, A088275, A095688, A107083, A108049, A108050, A108052, A108054.

Programs

  • Mathematica
    Do[ If[ PrimeQ[10^n + 27], Print[n]], {n, 3000}] (* Robert G. Wilson v, Jul 01 2005 *)

Extensions

a(6)=14081 from Robert Price, Mar 22 2010
Edited by Ray Chandler, Dec 23 2010
a(7)=65537 from Robert Price, Jan 29 2011

A110980 Integers n such that 10^n+99 is prime.

Original entry on oeis.org

1, 2, 4, 6, 13, 14, 16, 17, 19, 30, 31, 60, 68, 73, 113, 144, 276, 288, 364, 449, 473, 739, 833, 1171, 1732, 2292, 3912, 7673, 9458, 16982, 19751, 21479, 23837, 77726
Offset: 1

Views

Author

Julien Peter Benney (jpbenney(AT)ftml.net), Sep 30 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 "10w99".

Examples

			If n=6, we have 10^6+99 = 1000000+99 = 1000099, which is prime.

Links

Crossrefs

Cf. A049054, A088274, A088275, A095688, A107083, A108049, A108050, A108052, A108054.

Programs

  • Magma
    [n: n in [1..400]| IsPrime(10^n+99)]; // Vincenzo Librandi, Nov 02 2014
  • Mathematica
    Select[Range[78000],PrimeQ[10^#+99]&] (* Harvey P. Dale, Aug 23 2013 *)

Extensions

a(1)=1 added by Vladimir Joseph Stephan Orlovsky, May 02 2008
a(29)-a(33) from Robert Price, Mar 22 2010
a(34)=77726 from Robert Price, Mar 03 2011

A110918 Integers n such that 10^n+91 is a prime number.

Original entry on oeis.org

1, 2, 3, 4, 11, 12, 15, 19, 136, 144, 732, 5754, 6602, 23499, 39583, 74254, 93356, 94016
Offset: 1

Views

Author

Julien Peter Benney (jpbenney(AT)ftml.net), Oct 04 2005

Keywords

Comments

No additional terms < 100000.
See Kamada link - primecount.txt for terms, primesize.txt for discovery details including probable or proved primes - search on "10091".

Examples

			n = 4 is a member: 10^4+91 = 10000+91 = 10091, which is prime.

Links

Crossrefs

Cf. A049054, A088274, A088275, A095688, A107083, A108049, A108050, A108052, A108054.

Programs

Extensions

a(1)=1 added by Vladimir Joseph Stephan Orlovsky, May 02 2008
a(12)-a(15) from Robert Price, Dec 12 2010
Edited by Ray Chandler, Dec 23 2010
a(16)=74254 from Robert Price, Mar 03 2011
a(17)=92178 and a(18)=94016 from Robert Price, Apr 19 2011
a(17)=93356 corrected by Robert Price, Apr 19 2011
a(12) corrected by Tyler Busby, May 03 2024

A095680 13, together with primes of the form 10^k + 13 for some k >= 0.

Original entry on oeis.org

13, 113, 1013, 100000000000000013, 10000000000000000000000013, 1000000000000000000000000000000000000000000000000000000000000000000000000000000013
Offset: 1

Views

Author

Xavier Bury (x(AT)monsieurx.com), Jul 04 2004

Keywords

Comments

The next term has 141 digits. - Harvey P. Dale, May 26 2024

Crossrefs

See A095688 for the values of k.
Cf. A093011.

Programs

  • Mathematica
    Join[{13},Select[Table[FromDigits[PadRight[{1},n,0]]+13,{n,100}],PrimeQ]] (* Harvey P. Dale, May 26 2024 *)

Extensions

Corrected by N. J. A. Sloane, Dec 31 2016 at the suggestion of Harvey P. Dale.
Corrected by Harvey P. Dale, May 26 2024

A107084 Integers k such that 10^k + 33 is prime.

Original entry on oeis.org

1, 3, 6, 9, 10, 31, 47, 70, 281, 366, 519, 532, 775, 1566, 1627, 2247, 2653, 4381, 4571, 7513, 10581, 13239, 15393, 72267, 105515, 215802
Offset: 1

Views

Author

Julien Peter Benney (jpbenney(AT)ftml.net), Jun 08 2005

Keywords

Comments

The next term, if it exists, is > 39546. - Robert Price, Aug 21 2010
See Kamada link - primecount.txt for terms, primesize.txt for discovery details including probable or proved primes - search on "10033".
a(26) > 3*10^5. - Robert Price, Oct 26 2023

Examples

			For k = 3 we get 10^3 + 33 = 1000 + 33 = 1033, which is prime, so 3 is a term.

Links

Crossrefs

Cf. A049054, A088274, A088275, A095688, A108052, A108050, A108049, A108054.

Extensions

a(20)-a(23) from Robert Price, Aug 21 2010
Edited by Ray Chandler, Dec 23 2010
a(24) from Robert Price, Jan 29 2011
a(26) from Robert Price, Oct 26 2023
a(25) from Kamada data by Tyler Busby, Apr 16 2024

A111021 Integers k such that 7*10^k + 31 is a prime number.

Original entry on oeis.org

1, 8, 11, 143, 203, 2727, 2911, 3339, 17039
Offset: 1

Views

Author

Julien Peter Benney (jpbenney(AT)ftml.net), Oct 04 2005

Keywords

Comments

See Kamada link - primecount.txt for terms, primesize.txt for discovery details including probable or proved primes - search on "70031".
a(10) > 10^5. - Robert Price, Jan 28 2017

Examples

			k = 11 is a term because 7*10^11 + 31 = 7*100000000000 + 31 = 700000000000 + 31 = 700000000031, which is a prime.

Links

Crossrefs

Cf. A049054, A088274, A088275, A095688, A107083, A108049, A108050, A108052, A108054, A110980.

Programs

  • Magma
    [n: n in [1..300] | IsPrime(7*10^n+31)]; // Vincenzo Librandi, Jul 03 2016
  • Mathematica
    Select[Range[0, 10000], PrimeQ[7 10^# + 31] &] (* Vincenzo Librandi, Jul 03 2016 *)

Extensions

a(9) from Ray Chandler, Dec 23 2010
a(1) = 1 prepended by Vincenzo Librandi, Jul 03 2016

A135107 Integers n such that 10^n+97 is prime.

Original entry on oeis.org

1, 2, 3, 9, 10, 14, 19, 67, 94, 201, 241, 589, 934, 1151, 1179, 4957, 6329, 13621, 26425
Offset: 1

Views

Author

Julien Peter Benney (jpbenney(AT)gmail.com), Feb 12 2008

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 "10097".

Examples

			n = 3 is a member because 10^3+97 = 1000+97 = 1097, which is prime.

Links

Crossrefs

Cf. A095688, A108052, A108050, A108312, A107083, A108049, A108054.

Programs

Extensions

a(14)-a(19) from Robert Price, Nov 06 2010
Edited by Ray Chandler, Dec 23 2010
Showing 1-10 of 30 results. Next

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

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