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Primes p such that A007088(p) mod p is prime.
3

%I #9 Dec 08 2020 19:04:11

%S 3,17,19,29,31,71,79,83,103,113,151,211,229,293,331,337,347,349,421,

%T 439,449,457,607,659,683,691,739,743,809,839,883,911,977,1039,1051,

%U 1193,1249,1277,1283,1303,1367,1439,1451,1499,1567,1597,1609,1663,1747,1753,1861,2089,2137,2273,2309,2311

%N Primes p such that A007088(p) mod p is prime.

%H Robert Israel, <a href="/A339544/b339544.txt">Table of n, a(n) for n = 1..10000</a>

%e a(3) = 19 because 19 = 10011_2 and 10011 mod 19 = 17 which is prime.

%p filter:= proc(n) isprime(n) and isprime(convert(n,binary) mod n) end proc:

%p select(filter, [seq(i,i=3..10000,2)]);

%Y Cf. A007088.

%K nonn,base

%O 1,1

%A _J. M. Bergot_ and _Robert Israel_, Dec 08 2020