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A128886
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a(n) = prime(lucky(n)) - lucky(prime(n)).
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1
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-1, -2, 4, 2, 4, -2, 4, 22, 28, 4, 16, 2, 22, 14, 70, 48, 28, 40, 12, 2, 34, 24, 36, 42, 24, 16, 88, 82, 96, 68, 10, 46, 52, 70, 30, 28, 106, 84, 82, 62, 56, 78, 82, 106, 114, 118, 18, -40, 52, 66, 68, 52, 136, 70, 46, 52, 54, 64, 112, 78, 114, 94, 10, 50, 82, 82, 4, 136, 90, 74
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OFFSET
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1,2
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COMMENTS
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LINKS
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FORMULA
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EXAMPLE
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a(1) = Prime(Lucky(1)) - Lucky(Prime(1)) = Prime(1) - Lucky(2) = 2 - 3 = -1.
a(2) = Prime(Lucky(2)) - Lucky(Prime(2)) = Prime(3) - Lucky(3) = 5 - 7 = -2.
a(3) = Prime(Lucky(3)) - Lucky(Prime(3)) = Prime(7) - Lucky(5) = 17 - 13 = 4.
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PROG
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(Perl) use ntheory ":all"; say "$_ ", nth_prime(nth_lucky($_))-nth_lucky(nth_prime($_)) for 1..20; # Dana Jacobsen, Dec 21 2018
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CROSSREFS
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KEYWORD
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easy,sign
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AUTHOR
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EXTENSIONS
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Entries corrected starting at a(10) by R. J. Mathar, Oct 22 2010
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STATUS
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approved
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