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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
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, 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, 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
OFFSET
0,3
EXAMPLE
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.
MATHEMATICA
f[l_List] :=Append[l, Count[l, GCD[Max[l], Length[l]]]]; Nest[f, {1}, 105] (* Ray Chandler, Oct 16 2006 *)
CROSSREFS
Sequence in context: A109810 A365498 A367515 * A053238 A227783 A216321
KEYWORD
easy,nonn
AUTHOR
Leroy Quet, Oct 15 2006
EXTENSIONS
Extended by Ray Chandler, Oct 16 2006
STATUS
approved