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A139066 Primes of the form (8+k!)/8. 41
631, 45361, 453601, 59875201, 10897286401, 304112751022080001, 3231502092360622080001, 77556050216654929920001, 1105220249217462744317952000001, 332283946848556096005453226376826986289954816000000001 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
Numbers k for which (8+k!)/8 is prime see A151913
The next term (a(11)) has 174 digits. - Harvey P. Dale, May 10 2016
LINKS
MATHEMATICA
a = {}; Do[If[PrimeQ[(n! + 8)/8], AppendTo[a, (n! + 8)/8]], {n, 1, 50}]; a
Select[(8+Range[50]!)/8, PrimeQ] (* Harvey P. Dale, May 10 2016 *)
PROG
(PARI) for(k=4, 1e3, if(ispseudoprime(t=k!/8+1), print1(t", "))) \\ Charles R Greathouse IV, Jul 15 2011
CROSSREFS
Sequence in context: A252412 A002227 A251217 * A345557 A345811 A186898
KEYWORD
nonn
AUTHOR
Artur Jasinski, Apr 07 2008
EXTENSIONS
Corrected link to sequence of indexes. - Serge Batalov, Feb 17 2015
One more term (a(10)) added by Harvey P. Dale, May 10 2016
STATUS
approved

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Last modified May 29 19:17 EDT 2023. Contains 363042 sequences. (Running on oeis4.)