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A121360
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Smallest k such that A002217(k)=n.
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1
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2, 1, 8, 14, 26, 62, 134, 393, 1257, 4659, 9314, 27933, 167073, 334142, 4677862, 14033577, 56134292, 2133102298, 11788191218, 52541651594
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OFFSET
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1,1
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COMMENTS
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Least number which becomes prime or 0 or 4 after n-1 iterations of f(x) = sum of prime factors of x (cf. A001414). Agrees with A048133 except for the second term.
a(21) <= 536226160966. a(22) <= 2681130804805. a(23) <= 8512643845707. - Donovan Johnson
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LINKS
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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