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%I #15 Mar 30 2012 18:35:53
%S 29,37,47,73,79,83,97,113,149,163,167,263,277,283,311,317,349,359,389,
%T 421,433,449,461,509,521,607,617,641,761,941,953,983,1009,1021,1031,
%U 1033,1069,1097,1109,1153,1181,1193,1201,1213,1231,1237,1283,1301,1321
%N Primes p such that p is a quadratic residue modulo reverse(p) and reverse(p) is a quadratic residue modulo p.
%C Primes in A177872, excluding the palindromic primes A002385.
%H Eric W. Weisstein, <a href="http://mathworld.wolfram.com/QuadraticResidue.html">Quadratic Residue</a>
%H Eric W. Weisstein, <a href="http://mathworld.wolfram.com/JacobiSymbol.html">Jacobi Symbol</a>
%e Prime 317 is in the sequence because J(317, 713) = J(713, 317) = 1 where J is the Jacobi symbol.
%p with(numtheory): for n from 1 to 2500 do: s:=0:l:=length(n):for q from 0 to l do:x:=iquo(n, 10^q):y:=irem(x, 10):s:=s+y*10^(l-1-q): od: if s<>n and quadres(n,s)=1 and quadres(s, n)=1 and type(n, prime)=true then printf(`%d, `, n):else fi:od:
%Y Cf. A177872, A178399.
%K nonn,base
%O 1,1
%A _Michel Lagneau_, Dec 13 2010
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