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A261822
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Minimal nested palindromic primes with seed 5.
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2
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5, 151, 31513, 3315133, 11331513311, 191133151331191, 9919113315133119199, 39991911331513311919993, 353999191133151331191999353, 13539991911331513311919993531, 741353999191133151331191999353147
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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:
.......5
......151
.....31513
....3315133
..11331513311
191133151331191
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MATHEMATICA
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s = {5}; 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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