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A230046
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Palindromic primes with nondecreasing sum of digits.
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1
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2, 3, 5, 7, 151, 181, 191, 353, 373, 383, 727, 757, 787, 797, 17971, 19891, 19991, 38783, 74747, 75557, 76367, 76667, 77477, 77977, 78787, 78887, 79697, 79997, 1879781, 1895981, 1969691, 1987891, 1988891, 1998991, 3799973, 3899983, 3997993, 3998993, 7696967
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OFFSET
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1,1
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COMMENTS
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a(1) = 2; a(n+1) is the smallest palindromic prime with sum of digits >= sum of digits of a(n).
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LINKS
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MATHEMATICA
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a = {}; t = 0; Do[z = n*10^(IntegerLength[n] - 1) + FromDigits@Rest@Reverse@IntegerDigits[n]; If[PrimeQ[z], s = Apply[Plus, IntegerDigits[z]]; If[s >= t, t = s; AppendTo[a, z]]], {n, 10^5}]; a
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CROSSREFS
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KEYWORD
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nonn,base
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AUTHOR
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STATUS
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approved
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