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 A119655 a(0) = a(1) = 0. a(n) = number of earlier terms of the sequence which are not coprime to n. 1
 0, 0, 2, 2, 4, 2, 6, 2, 8, 3, 9, 2, 12, 2, 12, 7, 13, 2, 16, 2, 16, 8, 18, 2, 22, 2, 23, 8, 24, 2, 27, 2, 26, 11, 27, 3, 32, 2, 29, 14, 30, 2, 38, 2, 35, 14, 36, 2, 42, 7, 39, 16, 41, 2, 46, 6, 45, 19, 43, 2, 51, 2, 44, 24, 46, 8, 57, 2, 50, 24, 55, 2, 61, 2, 53, 25, 55, 13, 64, 2, 60 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0,3 LINKS Diana Mecum, Table of n, a(n) for n = 1..1199 [From Diana Mecum (diana.mecum(AT)gmail.com), Aug 15 2008] EXAMPLE Among the first 20 terms of the sequence there are 8 terms which are not coprime to 21 - a(0)=0, a(1)=0, a(6)=6, a(9)=3, a(10)=9, a(12)=12, a(14)=12 and a(15)=7. So a(21) = 8. MATHEMATICA a = {0, 0}; Do[AppendTo[a, Length[Select[a, GCD[Length[a], # ] > 1 &]]], {70}]; a - Stefan Steinerberger, Oct 16 2007 CROSSREFS Sequence in context: A137849 A118982 A129457 * A083260 A046523 A071364 Adjacent sequences:  A119652 A119653 A119654 * A119656 A119657 A119658 KEYWORD nonn AUTHOR Leroy Quet Jul 28 2006 EXTENSIONS More terms from Stefan Steinerberger, Oct 16 2007 Terms a(72) through a(1200) from Diana Mecum (diana.mecum(AT)gmail.com), Aug 15 2008 STATUS approved

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