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%I #11 Jul 21 2022 01:55:05
%S 1,12,24,225,392,819,1201,1645,1775
%N Numbers m such that 7^m reversed is prime.
%t Do[ If[ PrimeQ[ ToExpression[ StringReverse[ ToString[7^n] ] ] ], Print[n] ], {n, 1, 2500} ]
%o (Python)
%o from sympy import isprime
%o k, m, A058994_list = 1, 7, []
%o while k <= 10**3:
%o if isprime(int(str(m)[::-1])):
%o A058994_list.append(k)
%o k += 1
%o m *= 7 # _Chai Wah Wu_, Mar 09 2021
%o (PARI) isok(m) = isprime(fromdigits(Vecrev(digits(7^m)))) \\ _Mohammed Yaseen_, Jul 20 2022
%Y Cf. A059208, A071584.
%Y Numbers m such that k^m reversed is prime: A057708 (k=2), A350441 (k=4), A058993 (k=5), this sequence (k=7), A350442 (k=8), A058995 (k=13).
%K nonn,base,more
%O 1,2
%A _Robert G. Wilson v_, Jan 17 2001