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A261825
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Minimal nested palindromic primes with seed 8.
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2
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8, 181, 1218121, 15121812151, 111512181215111, 3311151218121511133, 133111512181215111331, 1113311151218121511133111, 1141113311151218121511133111411, 73114111331115121812151113311141137, 30273114111331115121812151113311141137203
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OFFSET
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1,1
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COMMENTS
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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.
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LINKS
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EXAMPLE
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As a triangle:
.........8
........181
......1218121
....15121812151
..111512181215111
3311151218121511133
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MATHEMATICA
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s = {8}; Do[NestWhile[# + 1 &, 1, ! PrimeQ[tmp = FromDigits[Join[#, IntegerDigits[Last[s]], Reverse[#]] &[IntegerDigits[#]]]] &]; AppendTo[s, tmp], {15}]; s
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CROSSREFS
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Cf. A261881 (seed 0, with guide to related sequences).
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KEYWORD
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nonn,easy,base
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AUTHOR
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STATUS
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approved
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