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%I #7 Jan 17 2014 17:25:50
%S 3244,32440,324400,324886,1109311,1979137,3244000,3248860,10212316,
%T 10255493,10282339,10306511,10503781,10573126,10657861,10692107,
%U 11093110,11145841,11171452,19791370,19855967,19875058,19912073
%N Numbers n such that the reversal of all five numbers n^1, n^2, n^3 n^4 and n^5 are primes.
%C This sequence is infinite because if n is in the sequence then for all natural numbers m, 10^m*n is in the sequence.
%C Contribution from _Farideh Firoozbakht_, Sep 29 2009: (Start)
%C 110218462 is the smallest term n such that the reversal of n^6 is also prime.
%C A165698 is a subsequence of this sequence such that for each term n reversal(n^6)
%C is also prime. (End)
%e 3244 is in the sequence because reversal(3244^k) for k=1,2,...,5
%e are respectively 4423, 63532501, 48705383143, 692349908447011,
%e and 422250654361652953 and these five numbers are primes.
%t Do[If[PrimeQ[FromDigits[Reverse[IntegerDigits[n]]]] && PrimeQ[FromDigits[Reverse[IntegerDigits[n^2]]]] && PrimeQ [FromDigits[Reverse[IntegerDigits[n^3]]]] && PrimeQ[FromDigits [Reverse[IntegerDigits[n^4]]]] && PrimeQ[FromDigits[Reverse [IntegerDigits[n^5]]]], Print[n]], {n, 32000000}]
%t Select[Range[20000000],And@@PrimeQ[FromDigits[Reverse[ IntegerDigits[ #]]]&/@ (#^Range[5])]&] (* _Harvey P. Dale_, Jan 17 2014 *)
%Y Cf. A118213.
%Y Cf. A165698. [From _Farideh Firoozbakht_, Sep 29 2009]
%K base,easy,nonn
%O 1,1
%A _Farideh Firoozbakht_, Apr 21 2006
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