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A081063 Number of numbers <= n that are 3-smooth or prime powers. 1
1, 2, 3, 4, 5, 6, 7, 8, 9, 9, 10, 11, 12, 12, 12, 13, 14, 15, 16, 16, 16, 16, 17, 18, 19, 19, 20, 20, 21, 21, 22, 23, 23, 23, 23, 24, 25, 25, 25, 25, 26, 26, 27, 27, 27, 27, 28, 29, 30, 30, 30, 30, 31, 32, 32, 32, 32, 32, 33, 33, 34, 34, 34, 35, 35, 35, 36, 36, 36, 36, 37, 38, 39 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

a(n) = #{A081061(k): 1<=k<=n}.

LINKS

Table of n, a(n) for n=1..73.

FORMULA

a(n)=A071521(n)+A065515(n)-A000523(n)-A062153(n)+1.

CROSSREFS

Cf. A003586, A000961.

Sequence in context: A137180 A128635 A100637 * A081304 A137721 A028904

Adjacent sequences:  A081060 A081061 A081062 * A081064 A081065 A081066

KEYWORD

nonn

AUTHOR

Reinhard Zumkeller, Mar 04 2003

STATUS

approved

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Last modified May 21 19:04 EDT 2013. Contains 225504 sequences.