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A089124
Largest prime factor of n^2 + 3.
1
2, 7, 3, 19, 7, 13, 13, 67, 7, 103, 31, 7, 43, 199, 19, 37, 73, 109, 13, 31, 37, 487, 19, 193, 157, 97, 61, 787, 211, 43, 241, 79, 13, 61, 307, 433, 7, 1447, 127, 229, 421, 31, 463, 277, 13, 163, 79, 769, 601, 2503, 31, 2707, 37, 139, 757, 73, 271, 37, 67, 1201, 19
OFFSET
1,1
REFERENCES
H. Rademacher, Lectures on Elementary Number Theory, pp. 33-38.
LINKS
FORMULA
a(n) = A006530(A117950(n)). - Jason Yuen, Aug 25 2024
MATHEMATICA
FactorInteger[#][[-1, 1]]&/@(Range[70]^2+3) (* Harvey P. Dale, Jun 17 2020 *)
PROG
(PARI) largeasqp3(m) = { for(a=1, m, y=a^2 + 3; f = factor(y); v = component(f, 1); v1 = v[length(v)]; print1(v1", ")) }
CROSSREFS
KEYWORD
easy,nonn
AUTHOR
Cino Hilliard, Dec 05 2003
STATUS
approved