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.

A123557 a(n) = A064688(n) - 1.

Original entry on oeis.org

0, 1, 2, 4, 11, 17, 37, 53, 103, 255, 339, 759, 1259, 1609, 2589, 5119, 9791, 12075, 22249, 32991, 40025, 70487, 101697, 173681, 345855, 483329, 570077, 789639, 927405, 1274117, 3725409, 5010687, 7755775, 8953855, 18108417, 20792119
Offset: 1

Views

Author

N. J. A. Sloane, based on email from Anthony Doran, Nov 18 2006

Keywords

Comments

This is the number of partitions of the n-th prime p into distinct odd parts that are less than p.

Examples

			a(4)=4 because the fourth prime (7) can be written in four different ways {6+1, 5+2, 4+3, 1+2+4}.
		

Crossrefs

Cf. A064688.

Programs

  • Mathematica
    Table[PartitionsQ[Prime[n]] - 1, {n, 50}] (* G. C. Greubel, Oct 15 2017 *)