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Primes p such that p | ((p-1)/2)! + 1.
3

%I #15 May 29 2022 20:28:57

%S 7,11,19,43,47,67,79,103,127,131,163,179,191,199,227,263,347,367,383,

%T 419,431,443,479,491,503,523,563,571,599,607,619,631,683,691,727,739,

%U 743,787,823,839,863,887,947,991,1019,1051,1087,1091,1123,1151,1187

%N Primes p such that p | ((p-1)/2)! + 1.

%C p | (p-1)! +1 iff p is a prime (Wilson's theorem). Note: all of the above primes are congruent to 3 (mod 4).

%C All primes == 3 mod 4 are members of either A055939 or A058302. - _Zak Seidov_, Jan 16 2007

%D J. B. Cosgrave, A Mersenne-Wieferich Odyssey, Manuscript, May 2022. See Section 18.5.

%H Amiram Eldar, <a href="/A055939/b055939.txt">Table of n, a(n) for n = 1..10000</a>

%t Select[ Range[ 1225 ], PrimeQ[ # ] && Mod[ ((# - 1)/2)! + 1, # ] == 0 & ]

%t Select[Prime[Range[200]],Divisible[((#-1)/2)!+1,#]&] (* _Harvey P. Dale_, Dec 17 2014 *)

%Y Cf. A002145, A058302.

%K nonn

%O 1,1

%A _Robert G. Wilson v_, Jul 22 2000