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%I #17 Dec 20 2020 16:45:41
%S 2,11,13,17,19,59,71,97,107,109,149,167,181,239,271,419,431,499,509,
%T 523,547,563,613,631,691,727,811,853,859,983,1009,1063,1087,1117,1151,
%U 1193,1229,1409,1427,1487,1559,1579,1601,1759,1823,1913,1973,2039,2099,2161,2237,2251,2309,2411,2437,2473
%N Primes p such that p*A007953(p)+1 is prime.
%H Robert Israel, <a href="/A338976/b338976.txt">Table of n, a(n) for n = 1..10000</a>
%e a(3) = 13 is a term because 13 and 13*(1+3)+1 = 53 are prime.
%p select(t -> isprime(t) and isprime(t*convert(convert(t,base,10),`+`)+1), [$2..10^4]);
%o (PARI) isok(p) = isprime(p) && isprime(p*sumdigits(p)+1); \\ _Michel Marcus_, Dec 18 2020
%Y Cf. A007953, A057147.
%Y Subsequence of A119449.
%K nonn,base
%O 1,1
%A _J. M. Bergot_ and _Robert Israel_, Dec 18 2020