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.

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A329532 Numbers k such that Product_{j=1..k} prime(j) + Product_{j=k+1..2*k} prime(j) is prime.

Original entry on oeis.org

1, 2, 3, 4, 24, 25, 45, 59, 1238, 2635, 4209, 5341
Offset: 1

Views

Author

Hugo Pfoertner, Nov 15 2019

Keywords

Comments

Based on discussion in primenumbers Yahoo group dated May 12, 2004, with a(9) = 1238 given by Jens Kruse Andersen.
Numbers k > 0 such that A002110(k) + A002110(2*k)/A002110(k) is prime. - Daniel Suteu, Nov 22 2019 [Edited by Michael S. Branicky, Apr 17 2025; else, 0 would be a term since A002110(0)=1 yields prime 2.]
a(13) > 10^4. - Michael S. Branicky, Apr 19 2025

Links

  • Cashogor, Payam Samidoost, David Cleaver, Jens Kruse Andersen, Creating Primes, digest of 9 messages in primenumbers Yahoo group, May 12, 2004. [Cached copy]

Crossrefs

Cf. A093429.

Programs

  • PARI
    for (k=1,100,if (ispseudoprime(prod(j=1,k,prime(j))+prod(j=k+1,k+k,prime(j))),print1(k,", ")))

Extensions

a(10) from Daniel Suteu, Nov 22 2019
a(11)-a(12) from Michael S. Branicky, Apr 17 2025
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Started in 1964 by Neil J. A. Sloane | Maintained by The OEIS Foundation Inc.

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