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 1-6 of 6 results.

A202113 Numbers n such that 90n + 61 is prime.

Original entry on oeis.org

0, 1, 2, 3, 4, 6, 7, 11, 13, 14, 20, 21, 23, 24, 25, 29, 31, 34, 36, 37, 39, 43, 44, 45, 46, 50, 51, 53, 55, 56, 58, 62, 64, 67, 69, 70, 71, 77, 81, 84, 90, 93, 94, 99, 101, 102, 104, 105, 106, 108, 109, 112, 114, 116, 119, 120, 123, 125, 127, 132, 135, 136
Offset: 1

Views

Author

J. W. Helkenberg, Dec 11 2011

Keywords

Comments

This sequence was generated by adding 14 Fibonacci-like sequences [See: PROG]. Looking at the format 90n+61 modulo 9 and modulo 10 we see that all entries of A142330 have digital root 7 and last digit 1. (Reverting the process is an application of the Chinese remainder theorem.) The 14 Fibonacci-like sequences are generated (via the p and q values given in the Perl program) from the base p,q pairs 61*91, 19*79, 37*43, 73*7, 11*71, 29*89, 47*53, 83*17, 13*67, 31*31, 49*49, 23*77, 41*41, 59*59.

Crossrefs

Cf. A181732, A198382, A195993, A196000, A196007, A201739, A201734, A201804, A201816, A201817, A201818, A201820, A201822, A202101, A202104, A202105, A202110, A202112.

Programs

  • Mathematica
    Select[Range[0, 200], PrimeQ[90 # + 61] &]
  • PARI
    is(n)=isprime(90*n+61) \\ Charles R Greathouse IV, Feb 17 2017

A202115 Numbers n such that 90n + 17 is prime.

Original entry on oeis.org

0, 1, 2, 5, 6, 7, 9, 12, 13, 14, 15, 18, 21, 22, 23, 25, 26, 27, 32, 35, 36, 37, 39, 40, 42, 46, 48, 50, 53, 54, 55, 57, 58, 60, 61, 65, 67, 70, 76, 77, 79, 81, 83, 84, 86, 88, 90, 92, 93, 97, 98, 104, 105, 111, 116, 123, 124, 127, 130, 131, 132, 133, 137
Offset: 1

Views

Author

J. W. Helkenberg, Dec 11 2011

Keywords

Links

Crossrefs

Cf. A181732, A198382, A195993, A196000, A196007, A201739, A201734, A201804, A201816, A201817, A201818, A201820, A201822, A202101, A202104, A202105, A202110, A202112, A202113, A202114.

Programs

  • Maple
    select(t -> isprime(90*t+17),[$0..1000]); # Robert Israel, Sep 02 2014
  • Mathematica
    Select[Range[0, 200], PrimeQ[90 # + 17] &]
  • PARI
    is(n)=isprime(90*n+17) \\ Charles R Greathouse IV, Feb 20 2017

A202114 Numbers n such that 90n + 53 is prime.

Original entry on oeis.org

0, 2, 5, 6, 7, 8, 9, 10, 13, 16, 17, 24, 26, 29, 30, 31, 33, 35, 42, 43, 44, 47, 48, 49, 51, 52, 55, 58, 64, 65, 68, 69, 70, 75, 77, 80, 82, 83, 85, 86, 87, 91, 93, 94, 96, 97, 99, 103, 104, 112, 113, 114, 120, 124, 126, 127, 132, 134, 135, 138, 140, 141
Offset: 1

Views

Author

J. W. Helkenberg, Dec 11 2011

Keywords

Comments

This sequence was generated by adding 12 Fibonacci-like sequences [See: PROG]. Looking at the format 90n+53 modulo 9 and modulo 10 we see that all entries of A142316 have digital root 8 and last digit 3. (Reverting the process is an application of the Chinese remainder theorem.) The 12 Fibonacci-like sequences are generated (via the p and q "seed" values entered into the PERL program) from the base p,q pairs 53*91, 19*17, 37*89, 73*71, 11*13, 29*67, 47*49, 83*31, 23*61, 41*43, 59*7, 77*79.

Crossrefs

Cf. A181732, A198382, A195993, A196000, A196007, A201739, A201734, A201804, A201816, A201817, A201818, A201820, A201822, A202101, A202104, A202105, A202110, A202112, A202113.

Programs

  • Mathematica
    Select[Range[0, 200], PrimeQ[90 # + 53] &]
  • PARI
    is(n)=isprime(90*n+53) \\ Charles R Greathouse IV, Feb 20 2017

A202116 Numbers n such that 90n + 89 is prime.

Original entry on oeis.org

0, 1, 2, 3, 4, 7, 8, 13, 15, 17, 18, 20, 21, 22, 25, 28, 29, 30, 31, 32, 36, 41, 44, 45, 46, 48, 51, 55, 58, 59, 62, 64, 65, 66, 69, 70, 72, 73, 77, 78, 83, 84, 86, 87, 88, 92, 97, 99, 105, 106, 107, 111, 112, 113, 116, 118, 119, 120, 121, 122, 123, 127, 129
Offset: 1

Views

Author

J. W. Helkenberg, Dec 11 2011

Keywords

Comments

This sequence was generated by adding 12 Fibonacci-like sequences [See: PROG?]. Looking at the format 90n+89 modulo 9 and modulo 10 we see that all entries of A142335 have digital root 8 and last digit 9. (Reverting the process is an application of the Chinese remainder theorem.) The 12 Fibonacci-like sequences are generated (via the p and q "seed" values entered into the PERL program) from the base p,q pairs 89*91, 19*71, 37*17, 73*53, 11*49, 29*31, 47*67, 83*13, 23*43, 41*79, 59*61, 77*7.

Crossrefs

Cf. A181732, A198382, A195993, A196000, A196007, A201739, A201734, A201804, A201816, A201817, A201818, A201820, A201822, A202101, A202104, A202105, A202110, A202112, A202113, A202114, A202115.

Programs

  • Mathematica
    Select[Range[0, 200], PrimeQ[90 # + 89] &]
  • PARI
    is(n)=isprime(90*n+89) \\ Charles R Greathouse IV, Jun 06 2017

A202129 Numbers n such that 90n + 71 is prime.

Original entry on oeis.org

0, 2, 4, 5, 7, 9, 10, 11, 12, 16, 17, 20, 23, 26, 28, 31, 33, 35, 38, 39, 40, 41, 42, 46, 48, 49, 52, 54, 55, 59, 60, 62, 63, 66, 67, 72, 76, 77, 82, 83, 87, 89, 90, 101, 103, 104, 105, 108, 111, 112, 114, 117, 118, 119, 125, 126, 129, 133, 137, 138, 140
Offset: 1

Views

Author

J. W. Helkenberg, Dec 11 2011

Keywords

Comments

This sequence was generated by adding 12 Fibonacci-like sequences [See: PROG?]. Looking at the format 90n+71 modulo 9 and modulo 10 we see that all entries of A142325 have digital root 8 and last digit 1. (Reverting the process is an application of the Chinese remainder theorem.) The 12 Fibonacci-like sequences are generated (via the p and q "seed" values entered into the Perl program) from the base p,q pairs 71*91, 19*89, 37*53, 73*13, 11*31, 29*49, 47*13, 83*67, 23*7, 41*61, 59*79, 77*43.

Crossrefs

Cf. A181732, A198382, A195993, A196000, A196007, A201739, A201734, A201804, A201816, A201817, A201818, A201820, A201822, A202101, A202104, A202105, A202110, A202112, A202113, A202114, A202115, A202116.

Programs

  • Mathematica
    Select[Range[0, 200], PrimeQ[90 # + 71] &]
  • PARI
    is(n)=isprime(90*n+71) \\ Charles R Greathouse IV, Jun 13 2017

A224864 Numbers n such that 90*n + 77 and 90*n + 79 are twin primes.

Original entry on oeis.org

3, 6, 15, 17, 18, 19, 20, 24, 29, 41, 45, 46, 60, 62, 68, 75, 82, 83, 89, 94, 95, 104, 111, 115, 122, 130, 146, 148, 152, 159, 169, 173, 174, 179, 199, 215, 218, 223, 227, 236, 239, 244, 255, 267, 276, 288, 305, 334, 353, 355, 356, 358, 369, 375, 381, 393, 398
Offset: 1

Views

Author

J. W. Helkenberg, Jul 22 2013

Keywords

Links

Crossrefs

Cf. A201822, A202112.

Programs

  • Mathematica
    Select[Range[0, 499], PrimeQ[90# + 77] && PrimeQ[90# + 79] &] (* copied from: Alonso del Arte, Jul 22 2013 *)
Select[Range[500],AllTrue[90#+{77,79},PrimeQ]&] (* Harvey P. Dale, Mar 19 2023 *)

Formula

A201822 INTERSECTS A202112.
Showing 1-6 of 6 results.

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