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A261821 Minimal nested palindromic primes with seed 4. 2
4, 11411, 1114111, 18111411181, 741811141118147, 1674181114111814761, 90167418111411181476109, 3901674181114111814761093, 14390167418111411181476109341, 9143901674181114111814761093419, 75914390167418111411181476109341957 (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

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

EXAMPLE

As a triangle:

.........4

.......11411

......1114111

....18111411181

..741811141118147

1674181114111814761

MATHEMATICA

s = {4}; 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: A058417 A352497 A191592 * A151587 A193137 A280545

Adjacent sequences:  A261818 A261819 A261820 * A261822 A261823 A261824

KEYWORD

nonn,easy,base

AUTHOR

Clark Kimberling, Sep 23 2015

STATUS

approved

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Last modified May 29 07:24 EDT 2022. Contains 354122 sequences. (Running on oeis4.)