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Palindromic good primes.
2

%I #13 May 16 2012 10:17:34

%S 5,11,101,191,727,929,30803,74047,77477,1123211,1150511,1338331,

%T 1444441,1684861,1761671,3065603,3392933,3503053,3541453,9779779,

%U 9845489,9926299,9927299,9932399,112959211,113030311,114535411,119676911

%N Palindromic good primes.

%C p is in the sequence iff p is in the sequences A028388 and A002385.

%C Thus, version 2 (A028388) of the definition of "good primes" is used here. [From Harvey P. Dale, May 13 2012]

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/GoodPrime.html">Good Prime</a>

%H C. Rivera, <a href="http://www.primepuzzles.net/puzzles/puzz_273.htm">Consecutive 'good' primes </a>

%e 11 is in the sequence because 11 is a palindromic number which is

%e a good prime(11^2>7*13, 11^2>5*17, 11^2>3*19 & 11^2>2*23).

%t b[n_]:=(For[m=1, m<n&&Prime[n]^2>Prime[n-m]Prime[n+m], m++ ];m); v={};Do[If[IntegerDigits[Prime[n]]==Reverse[IntegerDigits[Prime [n]]]&& b[n]==n, v=Append[v, Prime[n]];Print[v]], {n, 6986301}]

%Y Cf. A028388, A002385.

%K base,nonn

%O 1,1

%A _Farideh Firoozbakht_, Jun 28 2004