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 A129381 a(1)=1. a(n) = the number of earlier terms which are coprime to floor(sqrt(n)). 1
 1, 1, 2, 2, 2, 2, 2, 2, 8, 9, 9, 9, 9, 9, 9, 8, 8, 8, 8, 8, 8, 8, 8, 8, 24, 25, 25, 25, 25, 25, 25, 25, 25, 25, 25, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 12, 48, 49, 49, 49, 49, 49, 49, 49, 49, 49, 49, 49, 49, 49, 49, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32, 32 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,3 LINKS Table of n, a(n) for n=1..77. EXAMPLE Floor(sqrt(11)) = 3. So a(11) is the number of terms from among a(1),a(2),...a(10) which are coprime to 3. Terms a(1) through a(9) are each coprime to 3, so a(11) = 9. MAPLE a[1]:=1: for n from 2 to 100 do ct:=0: for j from 1 to n-1 do if igcd(a[j], floor(sqrt(n)))=1 then ct:=ct+1 else fi od: a[n]:=ct: od: seq(a[n], n=1..100); # Emeric Deutsch, Apr 16 2007 CROSSREFS Cf. A129382. Sequence in context: A299150 A202448 A339165 * A319991 A323275 A139514 Adjacent sequences: A129378 A129379 A129380 * A129382 A129383 A129384 KEYWORD nonn AUTHOR Leroy Quet, Apr 12 2007 EXTENSIONS More terms from Emeric Deutsch, Apr 16 2007 STATUS approved

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Last modified September 11 01:27 EDT 2024. Contains 375813 sequences. (Running on oeis4.)