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A160696
Largest k such that k^2 divides prime(n)+1.
5
1, 2, 1, 2, 2, 1, 3, 2, 2, 1, 4, 1, 1, 2, 4, 3, 2, 1, 2, 6, 1, 4, 2, 3, 7, 1, 2, 6, 1, 1, 8, 2, 1, 2, 5, 2, 1, 2, 2, 1, 6, 1, 8, 1, 3, 10, 2, 4, 2, 1, 3, 4, 11, 6, 1, 2, 3, 4, 1, 1, 2, 7, 2, 2, 1, 1, 2, 13, 2, 5, 1, 6, 4, 1, 2, 8, 1, 1, 1, 1, 2, 1, 12, 1, 2, 2, 15, 1, 1, 4, 6, 4, 2, 2, 10, 6, 1, 3, 2, 1, 2, 3, 2
OFFSET
1,2
COMMENTS
A160697 and A160698 give record values and where they occur.
LINKS
FORMULA
a(A049097(n)) = 1; a(A049098(n)) > 1;
a(n) = A000188(A008864(n)).
PROG
(PARI) a(n) = core(prime(n)+1, 1)[2]; \\ Michel Marcus, Nov 06 2022
CROSSREFS
KEYWORD
nonn
AUTHOR
Reinhard Zumkeller, May 24 2009
STATUS
approved