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%I #12 Jan 07 2018 21:39:00
%S 16,196,361,784,1024,1369,1444,1600,1681,3844,7225,7921,9025,9409,
%T 11236,14161,18496,19321,19600,36100,37249,38416,70756,73441,75076,
%U 76729,78400,78961,97969,99856,102400,105625,107584,109561,111556,112225
%N Squares which when reversed are primes (ignore leading zeros).
%H T. D. Noe, <a href="/A068989/b068989.txt">Table of n, a(n) for n=1..1000</a>
%e 40^2 = 1600. Reversing the digits we get 0061, which is the prime 61 padded with leading zeroes. Hence 1600 is in the sequence.
%e 41^2 = 1681. Reversing the digits we get 1861, which is a prime. Hence 1681 is in the sequence.
%e 42^2 = 1764. Reversing the digits we get 4671 = 3^3 * 173. So 1764 is not in the sequence.
%t Do[s = i^2; If[PrimeQ[FromDigits[Reverse[IntegerDigits[s]]]], Print[s]], {i, 1, 10^2}] (* Pe *)
%t Select[Range[100]^2, PrimeQ[FromDigits[Reverse[IntegerDigits[#]]]] &] (* _Alonso del Arte_, Jan 07 2018 *)
%o (PARI) isok(n) = issquare(n) && isprime(fromdigits(Vecrev(digits(n)))); \\ _Michel Marcus_, Jan 07 2018
%Y Cf. primes whose reversal is a square, A007488; numbers n such that n^2 reversed is a prime, A059007.
%K easy,nonn,base
%O 1,1
%A _Joseph L. Pe_, Mar 12 2002
%E More terms from _Zak Seidov_, Jan 26 2005
%E Edited by _N. J. A. Sloane_, Dec 23 2007
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