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Numbers x such that x + reverse of x is a prime.
7

%I #20 Nov 29 2014 03:08:53

%S 1,10,100,116,118,140,142,146,158,166,170,172,178,182,188,190,196,215,

%T 217,229,239,241,245,257,265,269,271,277,281,287,295,299,314,316,328,

%U 338,340,344,356,364,368,370,376,380,386,394,398,413,415,427,437,439

%N Numbers x such that x + reverse of x is a prime.

%H Zak Seidov, <a href="/A072366/b072366.txt">Table of n, a(n) for n = 1..10000</a>

%e 116 is a term because 116+611=727 is a prime.

%t Select[Range[1000], PrimeQ[ # + FromDigits[Reverse[IntegerDigits[ # ]]]] &] (* _Tanya Khovanova_, Jul 23 2007 *)

%o (PARI) isok(n) = isprime(n+subst(Polrev(digits(n)), x, 10)); \\ _Michel Marcus_, Nov 29 2014

%Y Cf. A056964, A072367.

%K base,easy,nonn

%O 1,2

%A _Shyam Sunder Gupta_, Jul 18 2002