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A123571 Smallest prime p such that p divides m^(m+1)+1, where m = (p-2n-1)/(2n). 1
13, 29, 79, 41, 41, 313, 421, 257, 541, 461, 1013, 673, 2341, 197, 661, 2113, 1361, 1009, 4447, 15161, 2857, 7789, 7499, 2113, 5101, 8269, 811, 9689, 1567, 1381, 2543, 31489, 3631, 23189, 9941, 10513, 16651, 21661, 84163, 5281, 13613, 1933, 22447 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Corresponding m = {5,6,12,4,3,25,29,15,29,22,45,27,89,6,21,...}.

LINKS

Table of n, a(n) for n=1..43.

EXAMPLE

a(1) = 13 because for m = (13-3)/2 = 5 prime 13 divides m^(m+1)+1 = 5^6+1 = 15626, but m^(m+1)+1 is not divisible by any prime p of the form p=2m+3 for m<5.

CROSSREFS

Sequence in context: A217197 A141196 A269785 * A209989 A269515 A166272

Adjacent sequences:  A123568 A123569 A123570 * A123572 A123573 A123574

KEYWORD

nonn

AUTHOR

Alexander Adamchuk, Nov 12 2006

EXTENSIONS

More terms from R. J. Mathar, Jan 17 2008

STATUS

approved

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Last modified January 28 00:32 EST 2020. Contains 331313 sequences. (Running on oeis4.)