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A067670
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Smallest prime of additive persistence n.
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0
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OFFSET
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0,1
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COMMENTS
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a(5) >= 29*10^2222222222222222222221-1, the next number of additive persistence 5 after A006050(5). (a(5) is not equal to A006050(5) because that number is divisible by 313.) - Pontus von Brömssen, Oct 17 2023
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REFERENCES
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H. J. Hindin, The additive persistence of a number, J. Rec. Math., 7 (No. 2, 1974), 134-135.
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LINKS
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FORMULA
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EXAMPLE
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a(2) = 19, 19 -> 10 -> 1, so 2 summation steps are required to reach a single-digit number.
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CROSSREFS
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KEYWORD
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hard,nonn,base
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AUTHOR
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STATUS
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approved
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