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A051453
Prime powers such that 1 + lcm(1,2,...,p^w) is prime.
0
1, 2, 3, 4, 5, 7, 9, 19, 25, 31, 47, 89, 127, 139, 1369, 2251, 3271, 4253, 4373, 4549, 5449, 13331, 37123, 55291
OFFSET
1,2
EXAMPLE
1 + lcm(1,2,..,89) = 718766754945489455304472257065075294401 is prime.
PROG
(PARI) ispp(n) = isprimepower(n) || n==1;
lista(nn) = {for (n=1, nn, if (ispp(n) && ispseudoprime(1+lcm([1..n])), print1(n, ", ")); ); } \\ Michel Marcus, Aug 26 2019
CROSSREFS
KEYWORD
nonn,more
AUTHOR
EXTENSIONS
Corrected and extended by Wouter Meeussen, Apr 18 2003
a(18)-a(22) from Jinyuan Wang, May 02 2020
a(23)-a(24) from Michael S. Branicky, Apr 22 2023
STATUS
approved