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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
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OFFSET
2,1
LINKS
Table of n, a(n) for n=2..50.
PrimeFan,
Listing of Esoteric Integer Sequences
MATHEMATICA
Flatten[Table[SPF[n^2 + (n + 1)], {n, 2, 50}]]
CROSSREFS
Sequence in context:
A217793
A299472
A285642
*
A352171
A225091
A225516
Adjacent sequences:
A209186
A209187
A209188
*
A209190
A209191
A209192
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.)