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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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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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Table of n, a(n) for n=0..4.
N. J. A. Sloane, The persistence of a number, J. Recreational Math., 6 (1973), 97-98.
Eric Weisstein's World of Mathematics, Additive Persistence
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FORMULA
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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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Cf. A003001, A045646, A006050.
Sequence in context: A217308 A105076 A103200 * A217071 A159879 A017185
Adjacent sequences: A067667 A067668 A067669 * A067671 A067672 A067673
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KEYWORD
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hard,more,nonn,base
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AUTHOR
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Shyam Sunder Gupta, Feb 23 2002
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STATUS
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approved
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