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A087583
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Distinct primes such that the absolute values of successive differences are distinct palindromes. a(n+1) is chosen to be < a(n) if such a prime exists, minimizing a(n)-a(n+1); otherwise the minimal a(n+1) > a(n) is chosen.
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0
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2, 3, 5, 11, 7, 29, 37, 103, 59, 271, 19, 107, 349, 127, 359, 157, 419, 137, 409, 701, 277, 691, 257, 661, 197, 641, 167, 773, 97, 733, 239, 1087, 461, 1117, 431, 1097, 643, 1259, 613, 1451, 967, 149, 977, 281, 2393, 61, 919, 41, 929, 31, 839, 3061, 619, 1487
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OFFSET
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0,1
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COMMENTS
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The sequence of absolute differences is 1,2,6,4,22,8,66,44.... Conjecture: this sequence is infinite and contains every even palindrome.
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LINKS
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EXAMPLE
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a(3) = 11: |11-5| = 6, a palindrome. The primes < 5 are excluded because they have already occurred in the sequence. 7 is excluded because |7-5| = 2 has already occurred as a difference.
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CROSSREFS
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KEYWORD
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base,nonn,easy
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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