OFFSET
1,1
COMMENTS
a(263) > 5000. - Jinyuan Wang, Mar 31 2020
LINKS
Jinyuan Wang, Table of n, a(n) for n = 1..262
EXAMPLE
1!/1 - 1 = 0 is not prime. 2!/1 - 1 = 1 is not prime. 3!/1 - 1 = 5 is prime. Thus, a(1) = 3.
MATHEMATICA
lnk[n_]:=Module[{k=1}, While[!PrimeQ[k!/n-1], k++]; k]; Array[lnk, 80] (* Harvey P. Dale, Aug 31 2015 *)
PROG
(PARI) a(n) = {for(k=1, oo, s=k!/n-1; if(floor(s)==s, if(ispseudoprime(s), return(k)))); }
CROSSREFS
KEYWORD
nonn
AUTHOR
Derek Orr, Apr 09 2014
STATUS
approved