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A348313
Primes q such that q^3+r^5+s^7 is also prime, where q,r,s are consecutive primes.
2
5, 11, 13, 71, 73, 97, 149, 223, 229, 283, 337, 353, 401, 409, 577, 827, 887, 1051, 1277, 1321, 1489, 1543, 1627, 1787, 1931, 2237, 2467, 2903, 3137, 3181, 3559, 3917, 4243, 4357, 4363, 4441, 4583, 4723, 4933, 5113, 5693, 5839, 5857, 6007, 6043, 6053, 6121
OFFSET
1,1
COMMENTS
Exponent values (3,5,7) given by the prime triplet of the form p, p+2, p+4.
EXAMPLE
5 is a term because 5^3+7^5+11^7 = 19504103 is prime;
11 is a term because 11^3+13^5+17^7 = 410711297 is prime.
MATHEMATICA
Select[Partition[Select[Range[6000], PrimeQ], 3, 1], PrimeQ[#[[1]]^3 + #[[2]]^5 + #[[3]]^7] &][[;; , 1]] (* Amiram Eldar, Oct 11 2021 *)
PROG
(Sage)
def Q(x):
if Primes().unrank(x)^3+Primes().unrank(x+1)^5+Primes().unrank(x+2)^7 in Primes():
return Primes().unrank(x)
A348313 = [Q(x) for x in range(0, 10^3) if Q(x)!=None]
(PARI) isok(p) = if (isprime(p), my(q=nextprime(p+1), r=nextprime(q+1)); isprime(p^3+q^5+r^7)); \\ Michel Marcus, Oct 11 2021
CROSSREFS
Sequence in context: A018607 A032481 A365502 * A352534 A236411 A073615
KEYWORD
nonn
AUTHOR
Dumitru Damian, Oct 11 2021
STATUS
approved