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A363751
Numbers k such that prime(k) mod k is prime.
2
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
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
KEYWORD
nonn
AUTHOR
Nicholas Leonard, Jun 19 2023
STATUS
approved