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A261822 Minimal nested palindromic primes with seed 5. 2
5, 151, 31513, 3315133, 11331513311, 191133151331191, 9919113315133119199, 39991911331513311919993, 353999191133151331191999353, 13539991911331513311919993531, 741353999191133151331191999353147 (list; graph; refs; listen; history; text; internal format)
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
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
KEYWORD
nonn,easy,base
AUTHOR
Clark Kimberling, Sep 23 2015
STATUS
approved

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Last modified March 29 02:23 EDT 2024. Contains 371264 sequences. (Running on oeis4.)