A377259 Least k such that for every integer i > k there are at least n composite numbers less than i and relatively prime to i.

30, 60, 90, 90, 120, 210, 210, 210, 210, 210, 210, 210, 210, 210, 240, 240, 240, 330, 420, 420, 420, 420, 420, 420, 420, 420, 420, 420, 420, 420, 420, 420, 420, 630, 630, 630, 630, 630, 630, 630, 630, 630, 630, 660, 660, 660, 660, 660, 660, 840, 840, 840, 840

Offset

1,1

Links

Table of n, a(n) for n=1..53.

Simeon Reich, On a problem in number theory, Mathematics Magazine 44 (1971), 277-278.

Example

For n = 1 we have a(n) = 30, because there are no composite numbers less than 30 and relatively prime to it, while there are for all larger numbers.

Crossrefs

Sequence in context: A383395 A074915 A073461 * A222618 A325992 A056954

Adjacent sequences: A377256 A377257 A377258 * A377260 A377261 A377262

Keyword

nonn

Author

Jeffrey Shallit, Oct 21 2024

Status

approved