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%I #14 Nov 07 2020 20:41:39
%S 3,29,37,41,53,71,73,83,107,149,157,173,179,197,199,277,283,311,317,
%T 367,401,433,491,499,509,563,643,683,727,769,773,809,829,839,877,953,
%U 1013,1063,1097,1109,1153,1171,1181,1297,1307,1361,1367,1399,1439,1453,1511,1543,1553,1567,1747,1847,1913
%N Primes p such that (p*s) mod q and (p*s) mod r are prime, where q,r,s are the next primes after p.
%H Robert Israel, <a href="/A338518/b338518.txt">Table of n, a(n) for n = 1..10000</a>
%e a(4) = 41 is a member because with p=41, q=43, r=47 and s=53 we have (41*53) mod 43 = 23 and (41*53) mod 47 = 11, and 23 and 11 are prime.
%p p2:= 2: p3:= 3: p4:= 5: R:= NULL: count:= 0:
%p while count < 100 do
%p p1:= p2; p2:= p3; p3:= p4;
%p p4:= nextprime(p4);
%p r2:= (p1*p4) mod p2;
%p r3:= (p1*p4) mod p3;
%p if isprime(r2) and isprime(r3) then
%p R:= R, p1; count:= count+1;
%p fi
%p od:
%p R;
%Y Cf. A338751.
%K nonn
%O 1,1
%A _J. M. Bergot_ and _Robert Israel_, Nov 06 2020
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