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Primes p such that A001414(p-1)*A001414(p+1) == q (mod p), where q is the prime before p.
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%I #5 Nov 30 2020 15:13:14

%S 3,13,17,29

%N Primes p such that A001414(p-1)*A001414(p+1) == q (mod p), where q is the prime before p.

%C Next term, if any, > 2*10^8.

%F a(n) = prime(k) where A339327(k) = prime(k-1).

%e a(3)=17 is in the sequence because it is prime and A001414(16)*A001414(18) = 8*8 = 64 == 13 (mod 17), and 13 is the prime before 17.

%p spf:= n -> add(t[1]*t[2],t=ifactors(n)[2]):

%p p:= 1: R:= NULL:

%p while p < 10^7 do

%p q:= p: p:= nextprime(p);

%p v:= spf(p-1)*spf(p+1) mod p;

%p if v = q then R:= R, p fi

%p od:

%p R;

%Y Cf. A001414, A339327

%K nonn,bref,more

%O 1,1

%A _Robert Israel_, Nov 30 2020