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A209189 Smallest prime factor of n^2 + n + 1. 0
7, 13, 3, 31, 43, 3, 73, 7, 3, 7, 157, 3, 211, 241, 3, 307, 7, 3, 421, 463, 3, 7, 601, 3, 19, 757, 3, 13, 7, 3, 7, 1123, 3, 13, 31, 3, 1483, 7, 3, 1723, 13, 3, 7, 19, 3, 37, 13, 3, 2551 (list; graph; refs; listen; history; text; internal format)
OFFSET
2,1
LINKS
MATHEMATICA
Flatten[Table[SPF[n^2 + (n + 1)], {n, 2, 50}]]
CROSSREFS
Sequence in context: A217793 A299472 A285642 * A352171 A225091 A225516
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Mar 05 2012
STATUS
approved

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Last modified March 28 04:13 EDT 2024. Contains 371235 sequences. (Running on oeis4.)