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 1-4 of 4 results.

A113832 Triangle read by rows: row n (n>=2) gives a set of n primes with the property that the pairwise averages are all primes, having the smallest largest element.

Original entry on oeis.org

3, 7, 3, 7, 19, 3, 11, 23, 71, 5, 29, 53, 89, 113, 3, 11, 83, 131, 251, 383, 5, 29, 113, 269, 353, 449, 509, 5, 17, 41, 101, 257, 521, 761, 881, 23, 431, 503, 683, 863, 1091, 1523, 1871, 2963, 31, 1123, 1471, 1723, 3463, 3571, 4651, 5563, 5743, 6991
Offset: 2

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Author

N. J. A. Sloane, Jan 25 2006

Keywords

Comments

If there is more than one set with the same smallest last element, choose the lexicographically earliest solution.
For distinct primes, the solution for n=5 is {5, 29, 53, 89, 173}.

Examples

			Triangle begins:
3, 7
3, 7, 19
3, 11, 23, 71
5, 29, 53, 89, 113
3, 11, 83, 131, 251, 383
5, 29, 113, 269, 353, 449, 509
The set of primes generated by {5, 29, 53, 89, 113} is {17, 29, 41, 47, 59, 59, 71, 71, 83, 101}.
		

References

  • Antal Balog, The prime k-tuplets conjecture on average, in "Analytic Number Theory" (eds. B. C. Berndt et al.) Birkhäuser, Boston, 1990, pp. 165-204. [Background]

Crossrefs

See A115631 for the case when all pairwise averages are distinct primes.

Extensions

More terms from T. D. Noe, Feb 01 2006

A113830 Leading term of a 2 X n generalized arithmetic progression (GAP) of primes with smallest last term.

Original entry on oeis.org

3, 7, 5, 11, 11, 47, 199, 199
Offset: 2

Views

Author

N. J. A. Sloane, Jan 25 2006

Keywords

Examples

			Here is the beginning of Granville's table:
n GAP Last term
2 3+8i+2j 13
3 7+24i+6j 43
4 5+36i+6j 59
5 11+96i+30j 227
6 11+42i+60j 353
7 47+132i+210j 1439
		

Crossrefs

A113833 Triangle read by rows: row n (n>=2) gives a set of n primes such that the averages of all subsets are distinct primes, having the smallest largest element.

Original entry on oeis.org

3, 7, 7, 19, 67, 5, 17, 89, 1277, 209173, 322573, 536773, 1217893, 2484733
Offset: 2

Views

Author

N. J. A. Sloane, Jan 25 2006

Keywords

Comments

If there is more than one set with the same smallest last element, choose the lexicographically earliest solution.
Note that, in each row, the n primes are equal modulo 4, 12, 12 and 120, respectively. - Row 5 from T. D. Noe, Aug 08 2006

Examples

			Triangle begins:
3, 7
7, 19, 67
5, 17, 89, 1277
		

References

  • Antal Balog, The prime k-tuplets conjecture on average, in "Analytic Number Theory" (eds. B. C. Berndt et al.) Birkhäuser, Boston, 1990, pp. 165-204. [Background]

Crossrefs

Extensions

Row 5 from T. D. Noe, Aug 08 2006

A153412 Differences in the first known 3 X 3 X 3 generalized arithmetic progression consisting of only prime numbers.

Original entry on oeis.org

2904, 3150, 7440
Offset: 1

Views

Author

Jonathan Vos Post, Dec 25 2008

Keywords

Crossrefs

Showing 1-4 of 4 results.