A261824 Minimal nested palindromic primes with seed 7.

7, 373, 93739, 129373921, 3212937392123, 34321293739212343, 353432129373921234353, 1335343212937392123435331, 1171335343212937392123435331711, 1051171335343212937392123435331711501, 74105117133534321293739212343533171150147

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:
........7
.......373
......93739
....129373921
..3212937392123
34321293739212343

Mathematica

s = {7}; 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: A082443 A082624 A332137 * A084001 A238632 A073908

Adjacent sequences: A261821 A261822 A261823 * A261825 A261826 A261827

Keyword

nonn,easy,base

Author

Clark Kimberling, Sep 23 2015

Status

approved