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A260250
Minimal nested palindromic primes with seed 000000000.
2
1300000000031, 713000000000317, 1471300000000031741, 12147130000000003174121, 3121471300000000031741213, 1213121471300000000031741213121, 33121312147130000000003174121312133, 323312131214713000000000317412131213323
OFFSET
2,1
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 having a(n-1) in the middle. Then (a(n)) is the sequence of minimal nested palindromic primes with seed s. (For A260250, the seed is not an integer, so that the offset is 2.)
LINKS
EXAMPLE
As a triangle:
000000000
1300000000031
713000000000317
1471300000000031741
12147130000000003174121,
3121471300000000031741213
1213121471300000000031741213121,
MATHEMATICA
s0 = "000000000"; s = {ToExpression[s0]}; Do[NestWhile[# + 1 &, 1, ! PrimeQ[tmp = FromDigits[Join[#, IntegerDigits[Last[s], 10, Max[StringLength[s0], Length[IntegerDigits[Last[s]]]]], Reverse[#]]&[IntegerDigits[#]]]] &]; AppendTo[s, tmp], {10}]; s0 <> ", " <> StringTake[ToString[Rest[s]], {2, -2}]
(* Peter J. C. Moses, Sep 23 2015 *)
CROSSREFS
Cf. A261881.
Sequence in context: A077300 A083407 A287262 * A088280 A011526 A061126
KEYWORD
nonn,base,easy
AUTHOR
Clark Kimberling, Sep 24 2015
STATUS
approved