A261822 Minimal nested palindromic primes with seed 5.

5, 151, 31513, 3315133, 11331513311, 191133151331191, 9919113315133119199, 39991911331513311919993, 353999191133151331191999353, 13539991911331513311919993531, 741353999191133151331191999353147

Offset

1,1

Comments

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 primes with seed s.

Links

Clark Kimberling, Table of n, a(n) for n = 1..200

Example

As a triangle:
.......5
......151
.....31513
....3315133
..11331513311
191133151331191

Mathematica

s = {5}; Do[NestWhile[# + 1 &, 1, ! PrimeQ[tmp = FromDigits[Join[#, IntegerDigits[Last[s]], Reverse[#]] &[IntegerDigits[#]]]] &]; AppendTo[s, tmp], {15}]; s
(* Peter J. C. Moses, Sep 01 2015 *)

Crossrefs

Cf. A261881 (seed 0, with guide to related sequences).

Sequence in context: A262655 A075598 A214691 * A105230 A222768 A208578

Adjacent sequences: A261819 A261820 A261821 * A261823 A261824 A261825

Keyword

nonn,easy,base

Author

Clark Kimberling, Sep 23 2015

Status

approved