A354842 a(n) is the smallest number k such that A354841(k) = n.

1, 4, 28, 1276, 9430, 463446, 24786396, 1340301868

Offset

0,2

Comments

Equivalently, the smallest integer k such that the number of primes between k and k+log(k), exclusive, is n.

Links

Table of n, a(n) for n=0..7.

Example

In the interval ]28; 28+log(28)[ = ]28; 31.332...[, there are two primes 29 and 31 and this is the first such interval with 2 primes, hence a(2) = 28.

Mathematica

seq[len_, nmax_] := Module[{s = Table[0, {len}], c = 0, n = 1, i}, While[c < len && n < nmax, i = Count[Range[n + 1, n + Log[n]], _?PrimeQ] + 1; If[i <= len && s[[i]] == 0, c++; s[[i]] = n]; n++]; s]; seq[5, 10^5] (* Amiram Eldar, Jun 25 2022 *)

Crossrefs

Cf. A354840 (similar, but between k and k+log(k)^2), A354841.

Sequence in context: A203279 A081792 A336622 * A084594 A334598 A000838

Adjacent sequences: A354839 A354840 A354841 * A354843 A354844 A354845

Keyword

nonn,more

Author

Bernard Schott, Jun 24 2022

Extensions

a(3)-a(5) from Alois P. Heinz, Jun 25 2022

a(6) from Amiram Eldar, Jun 25 2022

a(7) from David Consiglio, Jr., Jun 29 2022

Status

approved