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2, 5, 10, 17, 28, 51, 94, 161, 250, 351, 460, 671, 894, 1127, 1560, 2003, 2680, 3467, 4344, 5231, 6240, 7349, 8472, 9695, 11806, 14027, 16360, 19581, 22904, 26247, 29680, 34247, 39690, 47479, 55356, 64243, 73242, 82243, 91254, 101141, 111042
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OFFSET
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1,1
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COMMENTS
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Partial sums of primes in which neighboring digits differ at most by 1 (neighbors of 9 are 0 and 8 and 9). The subsequence of primes in this partial sum begins: 5, 17, 2003, 3467, 5231, 7349, 101141, 187367. What is the smallest value in this partial sum (after 5) which is itself a prime in which neighboring digits differ at most by 1? What is the analog in other bases?
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LINKS
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FORMULA
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EXAMPLE
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a(16) = 2 + 3 + 5 + 7 + 11 + 23 + 43 + 67 + 89 + 101 + 109 + 211 + 223 + 233 + 433 + 443 = 2003 is prime.
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MATHEMATICA
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Accumulate[Select[Prime[Range[1500]], Max[Abs[Differences[ IntegerDigits[ #]]] /.{9->1}] <2&]] (* Harvey P. Dale, Apr 01 2019 *)
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CROSSREFS
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KEYWORD
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base,easy,nonn
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AUTHOR
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STATUS
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approved
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