A389809 Sequence containing k-1 occurrences of prime(k) ordered by k.

3, 5, 5, 7, 7, 7, 11, 11, 11, 11, 13, 13, 13, 13, 13, 17, 17, 17, 17, 17, 17, 19, 19, 19, 19, 19, 19, 19, 23, 23, 23, 23, 23, 23, 23, 23, 29, 29, 29, 29, 29, 29, 29, 29, 29, 31, 31, 31, 31, 31, 31, 31, 31, 31, 31, 37, 37, 37, 37, 37, 37, 37, 37, 37, 37, 37

Offset

1,1

Comments

These are the denominators of the dense set of prime fractions discussed in A389586.

Links

Table of n, a(n) for n=1..66.

Example

First 8 rows, as a triangle:
   3
   5   5
   7   7   7
  11  11  11  11
  13  13  13  13  13
  17  17  17  17  17  17
  19  19  19  19  19  19  19
  23  23  23  23  23  23  23  23

Mathematica

Flatten[Table[Table[Prime[n], {n - 1}], {n, 12}]]

Crossrefs

Cf. A000027, A005145, A051697, A115732, A389586, A389810.

Sequence in context: A190136 A360635 A126611 * A164019 A307701 A103332

Adjacent sequences: A389806 A389807 A389808 * A389810 A389811 A389812

Keyword

nonn,tabl

Author

Clark Kimberling, Oct 19 2025

Status

approved