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A262498
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Minimal nested palindromic primes with seed 1111111.
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2
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1111111, 14111111141, 131411111114131, 91314111111141319, 389131411111114131983, 7238913141111111413198327, 16723891314111111141319832761, 381672389131411111114131983276183, 1638167238913141111111413198327618361, 1191638167238913141111111413198327618361911
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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 having 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:
1111111
14111111141
131411111114131
91314111111141319
389131411111114131983
7238913141111111413198327
16723891314111111141319832761
381672389131411111114131983276183
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MATHEMATICA
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s0 = "1111111"; 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}]
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CROSSREFS
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KEYWORD
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nonn,base,easy
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AUTHOR
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STATUS
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approved
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