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Primes p such that if q is the next prime, p*q mod (A004086(p)+A004086(q)) is prime.
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%I #12 Dec 30 2021 17:32:23

%S 3,5,7,11,13,23,29,31,53,59,71,73,83,89,101,107,109,127,137,149,163,

%T 173,181,191,193,211,223,227,233,239,257,271,277,281,283,307,317,367,

%U 373,389,409,419,431,449,461,463,467,479,491,509,521,523,547,577,587,593,607,613,631,641,643,653,659

%N Primes p such that if q is the next prime, p*q mod (A004086(p)+A004086(q)) is prime.

%H Robert Israel, <a href="/A350401/b350401.txt">Table of n, a(n) for n = 1..10000</a>

%e a(6) = 23 is a member because it is prime, the next prime is 29, and 23*29 mod (32+92) = 667 mod 124 = 47 is prime.

%p revdigs:= proc(n) local L,i,m;

%p L:= convert(n,base,10); m:= nops(L);

%p add(L[i]*10^(m-i),i=1..m)

%p end proc:

%p q:= 2: qr:= 2:

%p R:= NULL: count:= 0:

%p while count < 100 do

%p p:=q; pr:= qr;

%p q:= nextprime(p); qr:= revdigs(q); s:= p*q mod (pr+qr);

%p if isprime(s) then

%p R:= R, p; count:= count+1;

%p fi

%p od:

%p R;

%Y Cf. A004086.

%K nonn,base

%O 1,1

%A _J. M. Bergot_ and _Robert Israel_, Dec 28 2021