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A262659
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Minimal nested palindromic base-8 primes with seed 0; see Comments.
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3
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0, 13031, 511303115, 3351130311533, 333511303115333, 1033351130311533301, 1051033351130311533301501, 35105103335113031153330150153, 12135105103335113031153330150153121, 12012135105103335113031153330150153121021, 331201213510510333511303115333015015312102133
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OFFSET
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1,2
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COMMENTS
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Using only base-8 digits 0,1,2,3,4,5,6,7 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-8 primes with seed s.
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LINKS
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EXAMPLE
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a(3) = 511303115 is the least base-8 prime having a(2) = 13031 in its middle. Triangular format:
0
13031
511303115
3351130311533
333511303115333
1033351130311533301
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MATHEMATICA
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s = {0}; base = 8; 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 (* A262659 *)
Map[FromDigits[ToString[#], base] &, s] (* A262660 *)
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CROSSREFS
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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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