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A262651
Minimal nested palindromic base-6 primes with seed 3; see Comments.
4
3, 11311, 121131121, 5312113112135, 14531211311213541, 1145312113112135411, 51114531211311213541115, 5511145312113112135411155, 50551114531211311213541115505, 115055111453121131121354111550511, 51150551114531211311213541115505115
OFFSET
1,1
COMMENTS
Using only base-6 digits 0,1,2,3,4,5, 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 base-6 primes with seed s.
LINKS
EXAMPLE
a(3) = 121131121 is the least base-6 prime having a(2) = 11311 in its middle. Triangular format:
3
11311
121131121
5312113112135
14531211311213541
MATHEMATICA
s = {3}; base = 6; z = 20; Do[NestWhile[# + 1 &, 1, ! PrimeQ[tmp = FromDigits[Join[#, IntegerDigits[Last[s]], Reverse[#]] &[IntegerDigits[#, base]], base]] &];
AppendTo[s, FromDigits[IntegerDigits[tmp, base]]], {z}]; s (* A262651 *)
Map[FromDigits[ToString[#], base] &, s] (* A262652 *)
(* Peter J. C. Moses, Sep 01 2015 *)
CROSSREFS
Cf. A261881 (base 10), A262652, A262627.
Sequence in context: A375690 A171363 A280655 * A309246 A055379 A047777
KEYWORD
nonn,easy,base
AUTHOR
Clark Kimberling, Oct 27 2015
STATUS
approved