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Squares which can be represented as sum of a prime and its reverse in at least one way.
2

%I #15 Sep 14 2022 14:00:33

%S 4,121,625,94249,698896,1517824,5313025,6325225,6895876,6948496,

%T 7706176,15665764,63600625,95199049,170198116,449948944,522808225,

%U 562069264,1101576100,1183979281,1254505561,1271564281,1615718416,4045214404,9504885049,10989328900

%N Squares which can be represented as sum of a prime and its reverse in at least one way.

%H Giovanni Resta, <a href="/A227525/b227525.txt">Table of n, a(n) for n = 1..56</a> (terms < 2*10^12)

%e 121=29+92

%t SquareQ[n_Integer?Positive] := IntegerQ[Sqrt[n]] ; Union[Select[ Table[ Prime[x] + FromDigits[ Reverse[ IntegerDigits[ Prime[x]]]], {x, 5761455}], SquareQ]]

%t Select[Union[#+IntegerReverse[#]&/@Prime[Range[10^6]]],IntegerQ[Sqrt[#]]&] (* The program generates the first 12 terms of the sequence. *) (* _Harvey P. Dale_, Sep 14 2022 *)

%Y Cf. A067030.

%K nonn,base

%O 1,1

%A _Shyam Sunder Gupta_, Jul 14 2013

%E a(20)-a(26) from _Giovanni Resta_, Jul 18 2013