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A154525
Primes p such that lcm(1,2,3,...,p-2,p-1,p) + 1 is prime.
2
2, 3, 5, 7, 19, 31, 47, 89, 127, 139, 2251, 3271, 4253, 4373, 4549, 5449, 13331, 37123, 55291
OFFSET
1,1
FORMULA
A049537 INTERSECT A000040. - Ray Chandler, Jan 16 2009
MATHEMATICA
Select[Range[1000], PrimeQ[#] && PrimeQ[LCM@@Range[#]+1] &] (* Amiram Eldar, Nov 21 2018 *)
PROG
(PARI) isok(p) = isprime(p) && (isprime(lcm(vector(p, i, i)) + 1)); \\ Michel Marcus, Oct 26 2013, Feb 25 2014
CROSSREFS
KEYWORD
nonn
AUTHOR
Lekraj Beedassy, Jan 11 2009
EXTENSIONS
a(1)=2 inserted and a(8)-a(18) from Ray Chandler, Jan 16 2009
a(19) from Daniel Suteu, Nov 21 2018
STATUS
approved