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A145326
Least k such that f(n,k) is not a prime, where f(n,1)=4n-1 and f(n,k)=f(f(n,k-1)) for k>=2.
2
4, 2, 3, 1, 2, 2, 1, 2, 1, 1, 2, 2, 1, 1, 2, 1, 2, 3, 1, 2, 3, 1, 1, 1, 1, 2, 2, 1, 1, 1, 1, 2, 3, 1, 2, 1, 1, 2, 1, 1, 2, 2, 1, 1, 2, 1, 1, 2, 1, 2, 1, 1, 2, 1, 1, 2, 3, 1, 1, 2, 1, 1, 2, 1, 1, 3, 1, 2, 1, 1, 2, 1, 1, 1, 1, 1, 2, 2, 1, 1, 1, 1, 2, 1, 1, 1, 2, 1, 1, 2, 1, 2, 1, 1, 2, 2, 1, 1, 1, 1, 1, 1, 1, 1, 2
OFFSET
1,1
EXAMPLE
f(1,1)=3, f(1,2)=11, f(1,3)=43, f(1,4)=171, so a(1)=4.
CROSSREFS
Sequence in context: A326046 A231169 A297847 * A178915 A222221 A254043
KEYWORD
easy,nonn
AUTHOR
Clark Kimberling, Oct 07 2008
STATUS
approved