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 1-3 of 3 results.

A118839 Primes corresponding to the indices of A059791.

Original entry on oeis.org

2, 11, 17, 29, 199, 521, 3571, 9349, 103681, 3010349, 54018521, 370248451, 6643838879, 10749957121, 119218851371, 5600748293801, 688846502588399, 32361122672259149, 115561578124838522881, 412670427844921037470771
Offset: 1

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Author

Eric W. Weisstein, May 01 2006

Keywords

Links

  • Eric Weisstein's World of Mathematics, Phi-Prime

A050808 Numbers k such that floor(exp(k)) is prime.

Original entry on oeis.org

1, 2, 18, 50, 127, 141, 267, 310, 2290, 4487, 5391, 14025
Offset: 1

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Author

Patrick De Geest, Oct 15 1999

Keywords

Links

  • Eric Weisstein's World of Mathematics, e-Prime

Crossrefs

Cf. A050809 (the actual primes), A000149, A040016, A037028, A000227, A004791, A059791, A059792.

Programs

  • Mathematica
    Do[ If[ PrimeQ[ Floor[ \[ExponentialE]^n] ], Print[n] ], {n, 0, 4750} ]
Select[Range[15000],PrimeQ[Floor[Exp[#]]]&] (* Harvey P. Dale, Oct 16 2012 *)
  • PARI
    is(n)=ispseudoprime(exp(n)\1) \\ Charles R Greathouse IV, Jan 03 2014

Extensions

Corrected by Naohiro Nomoto, Feb 22 2001
More terms from Vladeta Jovovic, Feb 24 2001
More terms from Robert G. Wilson v, May 09 2001
a(11) = 5391 from Eric W. Weisstein, May 01 2006
a(12) from Donovan Johnson, Feb 04 2008

A168033 Primes p such that floor(phi^p) is prime.

Original entry on oeis.org

2, 5, 7, 11, 13, 17, 19, 31, 37, 41, 47, 53, 61, 71, 79, 113, 313, 353, 503, 613, 617, 863, 1097, 1361, 4787, 4793, 5851, 7741, 8467, 10691, 12251, 13963, 14449, 19469, 35449, 36779, 44507, 51169, 56003, 81671, 89849, 94823, 140057, 148091, 159521, 183089, 193201, 202667, 344293, 387433, 443609, 532277, 574219, 616787, 631181, 637751, 651821, 692147, 901657, 1051849
Offset: 1

Views

Author

Vladimir Joseph Stephan Orlovsky, Nov 17 2009

Keywords

Comments

Primes in A059791. - Charles R Greathouse IV, Jul 29 2011
Also primes in A001606. - Michel Marcus, Oct 21 2016

Crossrefs

Cf. A001606, A059791.

Programs

  • Magma
    [p: p in PrimesUpTo(2000)| IsPrime(Lucas(p))]; // Vincenzo Librandi, Jul 11 2019
  • Mathematica
    $MaxExtraPrecision=6!; Select[Prime[Range[5! ]],PrimeQ[Floor[GoldenRatio^# ]]&]
  • PARI
    phi=(1+sqrt(5))/2;forprime(p=2,1e3,if(isprime(floor(phi^p)),print1(p", "))) \\ Charles R Greathouse IV, Jul 29 2011

Extensions

a(22)-a(32) from Charles R Greathouse IV, Jul 29 2011
More terms (using A001606) from Joerg Arndt, Jul 11 2019
Showing 1-3 of 3 results.

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

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