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A124684
Primes of the form (p*q - 2)/5 where p and q are successive primes.
1
229, 1153, 14149, 15013, 189733, 214657, 253573, 350593, 514561, 522289, 725041, 853669, 1304581, 1453681, 2027569, 2183281, 2212453, 2469637, 3238513, 4166017, 4331941, 4467013, 5234689, 5510371, 5992933, 6102913, 8100097, 8130673
OFFSET
1,1
COMMENTS
These numbers times 5 are semiprimes.
LINKS
EXAMPLE
31*37 = 1147, 1147-2 = 1145, 1145/5 = 229 is a term.
MATHEMATICA
Select[(Times @@@ Partition[Prime[Range[1000]], 2, 1] - 2) / 5, PrimeQ] (* Amiram Eldar, May 26 2024 *)
PROG
(PARI) g(n, p=5) = { for(x=1, n, y=prime(x)*prime(x+1)-2; if(y%p==0, if(isprime(y/p), print1(y/p, ", ")))) }
CROSSREFS
Cf. A123921.
Sequence in context: A142608 A210514 A142665 * A332740 A178673 A028452
KEYWORD
easy,nonn
AUTHOR
Cino Hilliard, Dec 27 2006
STATUS
approved