A029972 Palindromic primes in base 4.

2, 3, 5, 17, 29, 59, 257, 373, 409, 461, 509, 787, 839, 887, 907, 991, 4289, 4561, 5189, 5669, 5861, 6133, 6217, 6553, 6761, 7309, 7517, 7789, 7853, 12899, 13171, 13591, 14327, 14347, 14411, 14683, 14747, 14891, 15083, 15227, 15439, 15647

Offset: 1

Author

Patrick De Geest

Keywords

• nonn
• base

Links

• John Cerkan, Table of n, a(n) for n = 1..10000
• P. De Geest, World!Of Palindromic Primes

Programs

Mathematica

Do[s = RealDigits[n, 4][[1]]; If[PrimeQ[n], If[FromDigits[s] == FromDigits[Reverse[s]], Print[n]]], {n, 1, 1600}]
(* Second program: *)
Select[Prime@ Range@ 1850, PalindromeQ@ IntegerDigits[#, 4] &] (* Michael De Vlieger, May 14 2017, Version 10 *)

PARI

isok(n) = my(d=digits(n, 4)); d == Vecrev(d); \\ Michel Marcus, May 14 2017