A363751 Numbers k such that prime(k) mod k is prime.

3, 4, 7, 8, 9, 13, 15, 16, 18, 20, 22, 24, 26, 28, 30, 31, 32, 33, 34, 36, 38, 39, 40, 42, 43, 44, 45, 47, 48, 49, 50, 51, 52, 53, 55, 57, 59, 60, 65, 66, 69, 72, 73, 74, 76, 78, 82, 84, 86, 88, 90, 92, 96, 98, 100, 102, 106, 108, 112, 116, 120, 126, 128, 130

Offset

1,1

Links

Table of n, a(n) for n=1..64.

Formula

a(n) = A000720(A363752(n)).

Example

9 is a term of this sequence as prime(9) mod 9 = 5, which is prime.

Mathematica

Table[If[PrimeQ[Mod[Prime[k], k]], k, Nothing], {k, 1, 100}]

Prog

(Python)
from sympy import prime, isprime
a363751=[]
for k in range(1, 101):
    if isprime(prime(k)%k):
        a363751.append(k)
(PARI) isok(k) = isprime(prime(k) % k); \\ Michel Marcus, Jun 19 2023

Crossrefs

Cf. A000720, A004648, A363752.

Sequence in context: A004201 A109054 A350690 * A129142 A359749 A075752

Adjacent sequences: A363748 A363749 A363750 * A363752 A363753 A363754

Keyword

nonn

Author

Nicholas Leonard, Jun 19 2023

Status

approved