login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A029972 Palindromic primes in base 4. 11

%I #12 May 14 2017 03:10:16

%S 2,3,5,17,29,59,257,373,409,461,509,787,839,887,907,991,4289,4561,

%T 5189,5669,5861,6133,6217,6553,6761,7309,7517,7789,7853,12899,13171,

%U 13591,14327,14347,14411,14683,14747,14891,15083,15227,15439,15647

%N Palindromic primes in base 4.

%H John Cerkan, <a href="/A029972/b029972.txt">Table of n, a(n) for n = 1..10000</a>

%H P. De Geest, <a href="http://www.worldofnumbers.com/palpri.htm">World!Of Palindromic Primes</a>

%t Do[s = RealDigits[n, 4][[1]]; If[PrimeQ[n], If[FromDigits[s] == FromDigits[Reverse[s]], Print[n]]], {n, 1, 1600}]

%t (* Second program: *)

%t Select[Prime@ Range@ 1850, PalindromeQ@ IntegerDigits[#, 4] &] (* _Michael De Vlieger_, May 14 2017, Version 10 *)

%o (PARI) isok(n) = my(d=digits(n, 4)); d == Vecrev(d); \\ _Michel Marcus_, May 14 2017

%K nonn,base

%O 1,1

%A _Patrick De Geest_

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recents
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified April 19 23:15 EDT 2024. Contains 371798 sequences. (Running on oeis4.)