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A060609 Repeatedly apply Euler phi to n-th prime; a(n) = highest power of 2 that is seen. 0
2, 2, 4, 2, 4, 4, 16, 2, 4, 4, 8, 4, 16, 4, 4, 8, 4, 16, 8, 8, 8, 8, 16, 16, 32, 16, 32, 8, 4, 16, 4, 16, 64, 8, 8, 16, 16, 2, 16, 8, 16, 16, 8, 64, 8, 16, 16, 8, 16, 8, 16, 32, 64, 16, 256, 16, 16, 8, 16, 32, 8, 16, 32, 32, 32, 16, 32, 32, 8, 16, 64, 16, 32, 32, 4, 8, 64, 32, 64, 128 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..80.

FORMULA

a(n)=A049116[A000040(n)]

EXAMPLE

n=100,p(100)=541, Phi-iteration chain is {541,540,144,48,16,8,4,2,1} with 9 terms. The largest power of 2 is the 5th term=16=a(100).

CROSSREFS

Cf. A000040, A000010, A049108, A049113, A049116, A003434.

Sequence in context: A116466 A116467 A079314 * A205138 A109526 A059214

Adjacent sequences:  A060606 A060607 A060608 * A060610 A060611 A060612

KEYWORD

easy,nonn

AUTHOR

Labos E. (labos(AT)ana.sote.hu), Apr 13 2001

STATUS

approved

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Last modified May 20 10:52 EDT 2013. Contains 225458 sequences.