A262659 Minimal nested palindromic base-8 primes with seed 0; see Comments.

0, 13031, 511303115, 3351130311533, 333511303115333, 1033351130311533301, 1051033351130311533301501, 35105103335113031153330150153, 12135105103335113031153330150153121, 12012135105103335113031153330150153121021, 331201213510510333511303115333015015312102133

Offset: 1

Author

Clark Kimberling, Oct 27 2015

Keywords

• nonn
• easy
• base

Comments

Using only base-8 digits 0,1,2,3,4,5,6,7 let s be a palindrome and put a(1) = s. Let a(2) be the least palindromic prime having s in the middle; for n > 2, let a(n) be the least palindromic prime have a(n-1) in the middle. Then (a(n)) is the sequence of minimal nested palindromic base-8 primes with seed s.

Examples

			a(3) = 511303115 is the least base-8 prime having a(2) = 13031 in its middle. Triangular format:
         0
       13031
     511303115
   3351130311533
  333511303115333
1033351130311533301
		

Links

• Clark Kimberling, Table of n, a(n) for n = 1..300

Crossrefs

Cf. A261881 (base 10), A262660, A262627.

Programs

Mathematica

s = {0}; base = 8; z = 20; Do[NestWhile[# + 1 &, 1, ! PrimeQ[tmp = FromDigits[Join[#, IntegerDigits[Last[s]], Reverse[#]] &[IntegerDigits[#, base]], base]] &];
AppendTo[s, FromDigits[IntegerDigits[tmp, base]]], {z}]; s  (* A262659 *)
Map[FromDigits[ToString[#], base] &, s]  (* A262660 *)
(* Peter J. C. Moses, Sep 01 2015 *)