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%I #5 Oct 01 2013 17:57:44
%S 0,0,0,54,63,27,36,54,0,594,594,792,792,0,594,495,693,693,99,198,396,
%T 495,297,297,396,396,396,99,495,297,99,693,99,99,693,8082,270,8352,
%U 540,810,360,7992,6444,8532,270,7812,5814,90,360,6354,5454,7542,5994
%N For each pair of twin primes (p,p+2) take the absolute value of the difference between p and p with digits reversed.
%C 9 divides each term.
%e (17, 19) is a pair of twin primes. The absolute value of 17 - 71 is in the sequence.
%t a={}; For[n=1, n<268,n++, If[Prime[n+1]-Prime[n]==2, AppendTo[a,Abs[Prime[n] -FromDigits[Reverse[IntegerDigits[Prime[n]]]]]]]]; a
%o (PARI) revdiff(n) = { forprime(x=1,n, if(isprime(x+2), a=vector(x); x1=x; z=0; ln=length(Str(x1)); for(y=1,ln, a[y] = x1%10; x1=floor(x1/10); ); for(y=1,ln, z += a[y]*10^(ln-y); ); print1(abs(z-x)" "); ) ) }
%K base,nonn,less
%O 1,4
%A _Cino Hilliard_, Nov 09 2003
%E Edited by _Stefan Steinerberger_, Jun 12 2007