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Search: id:A155875
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| A155875 |
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Smallest positive composite number such that a(n)-n is also composite |
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+0
2
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| 4, 9, 6, 9, 8, 9, 10, 15, 12, 15, 14, 15, 16, 21, 18, 21, 20, 21, 22, 25, 24
(list; graph; listen)
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OFFSET
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0,1
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COMMENT
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a(0)=4. Subtracting n=0 from a(0) gives 4-0=4, which is a composite number; subtracting n=1 from a(1) gives 9-1=8 which is composite; subtracting n=2 from a(2) gives 6-2=4 which is composite; subtracting n=3 from a(3) gives 9-3=6 which is composite; etc.
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CROSSREFS
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A155874, A122985
Sequence in context: A108533 A075635 A094243 this_sequence A105274 A089390 A053667
Adjacent sequences: A155872 A155873 A155874 this_sequence A155876 A155877 A155878
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KEYWORD
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base,easy,nonn
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AUTHOR
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Eric Angelini (eric.angelini(AT)skynet.be), Jan 29 2009
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