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A192261
Numbers n such that 4n+1 is a palindromic prime.
2
1, 25, 45, 78, 88, 93, 189, 199, 232, 2575, 2625, 2650, 3105, 3180, 3205, 3585, 3685, 4015, 4090, 4140, 4165, 4545, 4620, 7753, 7878, 8383, 8763, 8788, 8838, 8938, 9318, 9393, 9823, 17829, 17979, 18259, 18309, 18409, 18889, 19344, 19369, 19494, 19849, 19924
OFFSET
1,2
FORMULA
{n such that A016813(n) is in A002385}. [Jonathan Vos Post, Jul 17 2011]
MATHEMATICA
Select[Range[10000], PrimeQ[4#+1]&&PalindromeQ[4#+1]&] (* Harvey P. Dale, Jun 24 2023 *)
PROG
(PARI) is(n)=n==eval(concat(Vecrev(Str(n))))&&isprime(n);
for(n=1, 1e4, if(is(4*n+1), print1(n, ", "))) \\ Altug Alkan, Nov 04 2015
CROSSREFS
KEYWORD
nonn,base
AUTHOR
Matevz Markovic, Jul 02 2011
EXTENSIONS
Prior Mathematica program removed and more terms from Harvey P. Dale, Jun 24 2023
STATUS
approved