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%I #19 Jan 31 2022 06:48:34
%S 8,15,50,552,668,1011,1163,1215,2199,4230,7231,34310
%N Numbers m such that 8^m reversed is prime.
%C From _Bernard Schott_, Jan 30 2022: (Start)
%C If k is a term, then u = 3*k is a term of A057708, because 8^k = 2^(3k).
%C If k is an even term, then t = 3*k/2 is a term of A350441, because 8^k = 4^(3k/2). First examples: k = 8, 50, 552, 668, 4230, 34310, ... and corresponding t = 12, 75, 828, 1002, 6345, 51465, ... (End)
%t Select[Range[2200], PrimeQ[IntegerReverse[8^#]] &] (* _Amiram Eldar_, Dec 31 2021 *)
%o (PARI) isok(m) = isprime(fromdigits(Vecrev(digits(8^m))))
%o (Python)
%o from sympy import isprime
%o m = 8
%o for n in range (1, 2000):
%o if isprime(int(str(m)[::-1])):
%o print(n)
%o m *= 8
%Y Cf. A059003, A071586.
%Y Cf. Numbers m such that k^m reversed is prime: A057708 (k=2), A350441 (k=4), A058993 (k=5), A058994 (k=7), A058995 (k=13).
%K nonn,base,more
%O 1,1
%A _Mohammed Yaseen_, Dec 31 2021
%E a(10)-a(12) from _Amiram Eldar_, Dec 31 2021