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.

A275489 Most consecutive numbers that can be covered with arithmetic progressions of differences 2i+1, 1<=i<=n.

Original entry on oeis.org

1, 2, 4, 6, 10, 13, 17, 22, 30, 38, 45, 53, 63, 74, 83, 96, 112, 128, 145
Offset: 1

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Author

Robert Israel, Jul 29 2016

Keywords

Comments

Erdos and Selfridge conjecture that there is no covering system whose moduli are distinct odd integers > 1. This is equivalent to saying that a(n) is finite for all n.

Examples

			[1,2,3,4] can be covered by the arithmetic progressions 3k+1, 5k+2 and 7k+3 but [1,2,3,4,5] can't be covered by three arithmetic progressions with differences 3, 5 and 7, so  a(3) = 4.