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.

A342839 Numbers k such that there are more primes in the interval [4*k+1, 5*k] than there are in the interval [3*k+1, 4*k].

Original entry on oeis.org

1, 4, 7, 9, 10, 15, 16, 22, 23, 24, 25, 34, 36, 37, 39, 40, 47, 55, 56, 57, 58, 64, 67, 82, 84, 86, 87, 88, 91, 93, 94, 95, 96, 97, 98, 99, 100, 102, 104, 105, 106, 107, 130, 133, 134, 135, 136, 137, 138, 139, 140, 141, 142, 144, 146, 147, 148, 149, 150, 153
Offset: 1

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Author

Jon E. Schoenfield, Mar 23 2021

Keywords

Comments

After a(876) = 11895, there are no more terms < 100000.
Conjecture: a(876) = 11895 is the final term.
There exist eight terms k for which A342068(k) != 5: A342068(k) = 2 for k = 1; A342068(k) = 3 for k = 47, 67, 95, and 1323; and A342068(k)=4 for k = 22, 57, and 102.

Examples

			The intervals [1, 100], [101, 200], [201, 300], [301, 400], and [401, 500] contain 25, 21, 16, 16, and 17 primes, respectively (cf. A038822); 17 > 16, so 100 is a term of the sequence.
		

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