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A060611
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Smallest prime p such that n = A049108(p) = length of chain of iterates of Euler Phi starting with p.
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4
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2, 3, 5, 11, 17, 41, 83, 137, 257, 641, 1097, 2657, 5441, 10883, 17477, 40961, 65537, 140417, 295937, 557057, 1193537, 2384897, 4227137, 9548417, 17966357, 35946497, 71304257, 162174977, 305268737, 541073537, 1212153857, 2281701377
(list;
graph;
refs;
listen;
history;
text;
internal format)
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OFFSET
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2,1
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COMMENTS
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From 2nd to 12th term A007755 is the same as this sequence
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LINKS
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EXAMPLE
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n=13: a(13)=2657 is the smallest prime which gives a chain of length 13, 2657 -> 2656 -> 1312 -> 640 -> 256 -> 128 -> 64 -> 32 -> 16 -> 8 -> 4 -> 2 -> 1, while the smallest number having this property is A007755(13) = 2329 -> 2176 -> 1024 -> 512 -> 256 -> 128 -> 64 -> 32 -> 16 -> 8 -> 4 -> 2 -> 1.
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CROSSREFS
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A007755 has the same initial terms but is a different sequence.
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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Removed duplicate cross references, added link, reformulated example. - M. F. Hasler, Oct 25 2008
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STATUS
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approved
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