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Search: id:A097330
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| A097330 |
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In the sequence of prime numbers replace each term p by floor(p/2) and ceiling(p/2). |
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+0
2
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| 1, 1, 1, 2, 2, 3, 3, 4, 5, 6, 6, 7, 8, 9, 9, 10, 11, 12, 14, 15, 15, 16, 18, 19, 20, 21, 21, 22, 23, 24, 26, 27, 29, 30, 30, 31, 33, 34, 35, 36, 36, 37, 39, 40, 41, 42, 44, 45, 48, 49, 50, 51, 51, 52, 53, 54, 54, 55, 56, 57, 63, 64, 65, 66, 68, 69, 69, 70, 74, 75, 75, 76, 78, 79
(list; graph; listen)
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OFFSET
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1,4
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COMMENT
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a(2*n-1) + a(2*n) = A000040(n);
a(2*n) + a(2*n+1) = A024675(n-1) for n>1;
a(2*n+1) = A005097(n), a(2*(n+1)) = A006254(n).
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FORMULA
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a(n)=if n<3 then 1 else (prime((n+n mod 2)/2)+1)/2-n mod 2.
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EXAMPLE
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__ 2; __ 3; __ 5; __ 7; _ 11; _ 13; _ 17; __ 19; ...
1, 1; 1, 2; 2, 3; 3, 4; 5, 6; 6, 7; 8, 9; 9, 10; ...
1, 1, 1, 2, 2, 3, 3, 4, 5, 6, 6, 7, 8, 9, 9, 10, ....
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CROSSREFS
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Sequence in context: A116579 A156253 A060151 this_sequence A086861 A113865 A143738
Adjacent sequences: A097327 A097328 A097329 this_sequence A097331 A097332 A097333
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KEYWORD
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nonn
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AUTHOR
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Reinhard Zumkeller (reinhard.zumkeller(AT)gmail.com), Sep 17 2004
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