A098391 - OEIS

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A098391

a(n) = Log2(Log2(prime(n))), where Log2 = A000523.

0, 0, 1, 1, 1, 1, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,7

COMMENTS

a(n) = A000523(A098388(n)).

a(n) = A000523(A000523(A000040(n))).

LINKS

Table of n, a(n) for n=1..105.

CROSSREFS

Cf. A000040, A000523, A098388.

Sequence in context: A285481 A282622 A102572 * A071702 A225541 A355480

Adjacent sequences: A098388 A098389 A098390 * A098392 A098393 A098394

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, Sep 06 2004

STATUS

approved