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%I #8 Feb 03 2019 01:30:33
%S 1,2,2,4,4,6,7,4,2,5,11,4,6,7,11,8,5,18,19,6,6,7,19,12,12,13,18,19,12,
%T 12,16,16,10,16,14,18,17,26,32,35,11,39,22,15,30,31,19,45,25,34,51,22,
%U 24,22,19,52,53,29,32,57,31,34,59,17,45,26,34,26,35,47,36,30,37,45,21
%N a(1)=1. a(n) = number of positive integers <= n and coprime to (Sum_{k=1..n-1} a(k)).
%e The sum of the first 8 terms of the sequence is 30. So a(9) is the number of positive integers <= 9 and coprime to 30. There are two such integers, 1 and 7. So a(9) = 2.
%p a[1]:=1: for n from 2 to 100 do ct:=0: for j from 1 to n do if gcd(j,sum(a[k],k=1..n-1))=1 then ct:=ct+1 else ct:=ct: fi od: a[n]:=ct: od: seq(a[n],n=1..100); # _Emeric Deutsch_, Apr 13 2007
%K nonn
%O 1,2
%A _Leroy Quet_, Mar 30 2007
%E More terms from _Emeric Deutsch_, Apr 13 2007
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