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A144761 Integers n such that Phi(2, a(n)) = A144741(a(n)) > Phi(2, k) for 0 < k < a(n). 2
4, 6, 10, 12, 18, 24, 30, 36, 42, 54, 60, 78, 84, 90, 120, 150, 168, 180, 210, 240, 270, 300, 330, 390, 420, 510, 546, 570, 630, 780, 840, 990, 1050, 1170, 1260, 1320, 1470, 1650, 1680, 1890, 2100, 2310, 2730, 3150, 3360, 3570, 3990, 4290, 4620, 4830 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Subset of A065385.

The first three terms are semiprimes and the number of factors gradually increases. All except four and ten are multiples of six.

LINKS

Table of n, a(n) for n=1..50.

CROSSREFS

Cf. A051953, A065385, A144741, A144742

Sequence in context: A243864 A024995 A086298 * A295523 A122171 A310580

Adjacent sequences:  A144758 A144759 A144760 * A144762 A144763 A144764

KEYWORD

easy,nonn

AUTHOR

Reikku Kulon, Sep 20 2008

STATUS

approved

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Last modified September 19 18:06 EDT 2020. Contains 337181 sequences. (Running on oeis4.)