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 A128267 a(0) = 1; a(n) = GCD((number of earlier terms which are coprime to n),(sum of the earlier terms which are coprime to n)). 2
 1, 1, 2, 1, 3, 1, 4, 1, 2, 1, 1, 1, 8, 1, 2, 1, 1, 1, 12, 1, 2, 1, 1, 1, 16, 1, 2, 5, 1, 1, 19, 1, 1, 1, 1, 1, 2, 1, 3, 1, 1, 1, 2, 1, 1, 1, 1, 1, 1, 1, 2, 1, 2, 1, 1, 1, 1, 1, 1, 1, 2, 1, 2, 2, 2, 1, 1, 1, 1, 6, 1, 1, 2, 1, 1, 1, 8, 11, 8, 1, 2, 1, 12, 1, 1, 1, 9 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 LINKS Diana L. Mecum, Table of n, a(n) for n = 0..1677 EXAMPLE The terms among {a(0),a(1),...a(7)} that are coprime to 8 are a(0)=1, a(1)=1, a(3)=1, a(4)=3, a(5)=1 and a(7)=1. There are 6 such terms and the sum of these terms is 8. So a(8) = GCD(6,8) = 2. CROSSREFS Cf. A128268. Sequence in context: A102547 A177812 A087267 * A028920 A055396 A057499 Adjacent sequences:  A128264 A128265 A128266 * A128268 A128269 A128270 KEYWORD nonn AUTHOR Leroy Quet Feb 22 2007 EXTENSIONS More terms from Diana L. Mecum, Aug 06 2012 STATUS approved

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