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A139060
Primes of the form (4+k!)/4.
11
7, 31, 181, 1556755201, 12772735542927360001, 3877802510832746496000001, 65782709233423382541804503040000001, 203978820811974433586402817399028973568000000001
OFFSET
1,1
COMMENTS
For numbers k for which (4+k!)/4 is prime see A139061.
LINKS
FORMULA
a(n) = A139151(A139061(n)). - Amiram Eldar, Oct 13 2024
MATHEMATICA
a = {}; Do[If[PrimeQ[(n! + 4)/4], AppendTo[a, (n! + 4)/4]], {n, 1, 50}]; a
Select[(4+Range[100]!)/4, PrimeQ] (* Harvey P. Dale, Oct 05 2016 *)
PROG
(PARI) for(k=4, 1e3, if(ispseudoprime(t=k!/4+1), print1(t", "))) \\ Charles R Greathouse IV, Jul 15 2011
KEYWORD
nonn
AUTHOR
Artur Jasinski, Apr 07 2008
STATUS
approved