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A120927 a(n) = floor(semiprime(n)/n). 2
4, 3, 3, 2, 2, 2, 3, 2, 2, 2, 3, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 2, 3, 3, 2, 2, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 2, 2, 3, 3, 2, 3, 3, 2, 2, 2, 3, 3, 3, 2, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

The ratio is an integer for n = 1, 2, 3, 11, 43, 53, ...

LINKS

Andrew Howroyd, Table of n, a(n) for n = 1..1000

FORMULA

a(n) = floor(A001358(n)/n).

EXAMPLE

a(1) = floor(4/1) = 4 because 4 is the first semiprime.

a(2) = floor(6/2) = 3 because 6 is the second semiprime.

a(3) = floor(9/3) = 3 because 9 is the third semiprime.

a(4) = floor(10/4) = 2 because 4 is the fourth semiprime.

PROG

(PARI) seq(n)={my(a=vector(n), k=1, i=0); while(k<=#a, i++; if(bigomega(i)==2, a[k]=i\k; k++)); a} \\ Andrew Howroyd, Nov 08 2019

CROSSREFS

Cf. A001358.

Sequence in context: A327869 A196274 A073871 * A241180 A117323 A016502

Adjacent sequences:  A120924 A120925 A120926 * A120928 A120929 A120930

KEYWORD

easy,nonn,changed

AUTHOR

Jonathan Vos Post, Aug 18 2006

EXTENSIONS

Terms a(61) and beyond from Andrew Howroyd, Nov 08 2019

STATUS

approved

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Last modified November 20 10:09 EST 2019. Contains 329334 sequences. (Running on oeis4.)