login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo

Thanks to everyone who made a donation during our annual appeal!
To see the list of donors, or make a donation, see the OEIS Foundation home page.

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A055939 Primes p such that p | ((p-1)/2)! + 1. 3
7, 11, 19, 43, 47, 67, 79, 103, 127, 131, 163, 179, 191, 199, 227, 263, 347, 367, 383, 419, 431, 443, 479, 491, 503, 523, 563, 571, 599, 607, 619, 631, 683, 691, 727, 739, 743, 787, 823, 839, 863, 887, 947, 991, 1019, 1051, 1087, 1091, 1123, 1151, 1187 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

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

All primes == 3 mod 4 are members of either A055939 or A058302. - Zak Seidov, Jan 16 2007

LINKS

Table of n, a(n) for n=1..51.

MATHEMATICA

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

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

CROSSREFS

Cf. A058302.

Sequence in context: A103802 A038984 A165549 * A154555 A285016 A162857

Adjacent sequences:  A055936 A055937 A055938 * A055940 A055941 A055942

KEYWORD

nonn

AUTHOR

Robert G. Wilson v, Jul 22 2000

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified January 19 20:41 EST 2020. Contains 331066 sequences. (Running on oeis4.)