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A167419
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Exchange adjacent nonprimes and primes.
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0
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2, 1, 4, 3, 6, 5, 8, 7, 9, 11, 10, 13, 12, 14, 15, 17, 16, 19, 18, 20, 21, 23, 22, 24, 25, 26, 27, 29, 28, 31, 30, 32, 33, 34, 35, 37, 36, 38, 39, 41, 40, 44, 43, 45, 47, 46, 48, 49, 50, 51, 53, 52, 54, 55, 56, 57, 59, 58, 61, 60, 62, 63, 65, 65, 67, 66, 68, 69, 71, 70, 73, 72
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OFFSET
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1,1
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COMMENTS
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If we have consecutive numbers, one prime and one nonprime, swap them. So after the initial 2,1,4,3,6,5,8,7 we have "if n is prime, a(n) = n-1; if n+1 is prime, a(n) = n+1, otherwise a(n) = n".
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LINKS
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Table of n, a(n) for n=1..72.
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CROSSREFS
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Cf. A014681
Sequence in context: A076981 A147965 A167542 * A114285 A014681 A103889
Adjacent sequences: A167416 A167417 A167418 * A167420 A167421 A167422
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KEYWORD
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easy,nonn
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AUTHOR
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Giovanni Teofilatto, Nov 03 2009
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EXTENSIONS
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Edited by Franklin T. Adams-Watters, Nov 04 2009
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STATUS
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approved
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