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%I #10 Mar 23 2021 05:41:04
%S 43,53,79,103,227,769,977,1303,2179,2803,3019,5179,5503,8089,8101,
%T 10651,10789,13339,13729,14419,16069,17053,17341,18077,23203,25111,
%U 26153,26161,32839,34127,34351,34519,38791,39103,44027,54319,56629,57503,59053,60811,62869,63079,64579,64591,65203,69019
%N Primes p such that p, x+y, x-y, p-x*y and p+x*y are prime, where y = p mod 5 and x = (p-y)/5.
%C If y = 4, x+y = p-x*y.
%H Robert Israel, <a href="/A342771/b342771.txt">Table of n, a(n) for n = 1..10000</a>
%e a(3) = 79 is a term because y = 79 mod 5 = 4, x = (79-4)/5 = 15, and 15-4 = 11. 15+4 = 19, 79-4*15 = 19 and 79+4*15 = 139 are prime.
%p filter:= proc(n) local a,b;
%p b:= n mod 5;
%p a:= (n-b)/5;
%p isprime(a+b) and isprime(a-b) and isprime(n-a*b) and isprime(n+a*b)
%p end proc:
%p select(filter, [seq(ithprime(i),i=1..1000)]);
%K nonn
%O 1,1
%A _J. M. Bergot_ and _Robert Israel_, Mar 21 2021
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