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Search: id:A161994
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| A161994 |
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Composites with an even remainder if divided through the sum of their prime factors. |
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+0
1
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| 4, 8, 16, 18, 20, 24, 27, 28, 30, 32, 36, 42, 44, 48, 50, 54, 56, 60, 64, 66, 70, 72, 75, 78, 80, 84, 90, 98, 99, 100, 102, 105, 108, 110, 114, 120, 126, 128, 130, 132, 138, 140, 144, 150, 152, 154, 156, 160, 162, 168, 170, 174, 180, 182, 184, 186, 190, 192, 195, 196, 198
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OFFSET
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1,1
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COMMENT
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The composites A002808(k) have prime factor sums A046343(k). The sequence
of remainders, A002808(k) mod A046343(k) = 0, 1, 2, 3, 3, 5, 5, 7, 0,... is scanned
for the even terms, occurring at positions k = 1, 3, 9, 10, 11,..., and the associated
A002808(k) are put into the sequence.
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EXAMPLE
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The first composite is 4=2*2 and 4 mod (2+2) =0 is even, so 4 is added to the sequence.
The second composite is 6=2*3 and 6 mod (2+3) = 1 is odd, so 6 is not added.
The third composite is 8=2*2*2 and 8 mod (2+2+2) = 2 is even, so 8 is added.
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CROSSREFS
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Cf. A002808, A046343.
Sequence in context: A072603 A123535 A065192 this_sequence A070738 A055744 A141718
Adjacent sequences: A161991 A161992 A161993 this_sequence A161995 A161996 A161997
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KEYWORD
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nonn,easy
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AUTHOR
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Juri-Stepan Gerasimov (2stepan(AT)rambler.ru), Jun 24 2009
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EXTENSIONS
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104 removed by R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Sep 23 2009
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