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A122066 a(0)=1. a(n) = the number of earlier terms equal to GCD(a(k),n), where a(k) is the largest term among terms a(0) through a(n-1). 0

%I #11 Nov 01 2019 12:52:00

%S 1,1,2,2,2,2,4,2,1,3,5,3,3,3,3,1,4,4,4,4,1,5,5,5,5,5,5,5,5,5,10,5,5,5,

%T 5,14,5,5,5,5,5,5,1,6,5,6,5,6,5,0,5,6,5,6,5,6,1,7,5,7,5,7,5,3,5,7,5,7,

%U 5,7,1,8,5,8,5,8,5,6,5,8,5,8,5,8,1,9,5,9,5,9,5,6,5,9,5,9,5,9,1,10,5,10,5,10

%N a(0)=1. a(n) = the number of earlier terms equal to GCD(a(k),n), where a(k) is the largest term among terms a(0) through a(n-1).

%e The largest term among terms a(0) through a(9) is a(6)=4. GCD(4,10)=2. So a(10) is the number of earlier terms equal to 2. a(2) =a(3) =a(4) =a(5) =a(7) =2. So a(10) = 5.

%t f[l_List] :=Append[l, Count[l, GCD[Max[l], Length[l]]]];Nest[f, {1}, 105] (* _Ray Chandler_, Oct 16 2006 *)

%K easy,nonn

%O 0,3

%A _Leroy Quet_, Oct 15 2006

%E Extended by _Ray Chandler_, Oct 16 2006

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