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A261821
Minimal nested palindromic primes with seed 4.
2
4, 11411, 1114111, 18111411181, 741811141118147, 1674181114111814761, 90167418111411181476109, 3901674181114111814761093, 14390167418111411181476109341, 9143901674181114111814761093419, 75914390167418111411181476109341957
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:
.........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
KEYWORD
nonn,easy,base
AUTHOR
Clark Kimberling, Sep 23 2015
STATUS
approved