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%I #28 Nov 22 2024 10:59:45
%S 13,17,31,107,1279,9941,3021377,13466917
%N Exponents of Mersenne primes that are emirps.
%C The just discovered Mersenne exponent 136279841 is also an emirp. However, it cannot be included as the next member of the sequence as there are Mersenne exponents over 70000000 that have not been double checked yet.
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/Emirp.html">Emirp</a>.
%H Wikipedia, <a href="https://en.wikipedia.org/wiki/Emirp">Emirp</a>.
%e 107 is a term because it is in A000043 and in A006567.
%t Select[MersennePrimeExponent[Range[48]], PrimeQ[p=FromDigits[Reverse[IntegerDigits[#]]]] && p!=# &] (* _Stefano Spezia_, Nov 02 2024 *)
%Y Intersection of A000043 and A006567.
%K nonn,base,more
%O 1,1
%A _Rodolfo Ruiz-Huidobro_, Oct 29 2024