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A128268
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a(0)=1; a(n) = lcm((number of earlier terms which are coprime to n), (sum of the earlier terms which are coprime to n)).
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3
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1, 1, 2, 12, 2, 90, 2, 770, 2, 5460, 2, 27870, 2, 86268, 2, 144, 2, 120632, 2, 4584054, 2, 1568502, 2, 147057998, 2, 1073923452, 2, 1324614852, 2, 74007713886, 2, 226457341710, 2, 735893320, 2, 2038112823132, 2, 86649033201030, 2, 4415363800
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OFFSET
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0,3
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LINKS
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EXAMPLE
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Every term among {a(0),a(1),...a(6)} is coprime to 7. There are 7 such terms. And the sum of these terms is 110. So a(8) = lcm(7,110) = 770.
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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EXTENSIONS
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STATUS
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approved
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