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A166483 Numerator of sequence of ratios of semiprimes and multiples thereof in intervals of length 4*6, 4*6*9, 4*6*9*10,...[A112141] to the length of the interval. See example below. The first few ratios are: 1/4,8/24, 84/216,912/2160,... 0
1, 8, 24, 912, 13344, 21240, 4536000 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Conjecture: sequences for 2-ads, 3-ads (composites of 3 primes), 4-ads, etc., converge to 1/2, 1/4, 1/8,..., respectively.

LINKS

Table of n, a(n) for n=1..7.

EXAMPLE

Example: For the second ratio, 4*6 is the denominator (product of first two semiprimes), and there 8 multiples of the semiprimes 4,6 in the interval, including those two semiprimes, repetitions (such as 4*3, 2*6) are only counted once. The ratio is then 8/24. The first few analogous ratios for 3-ads are: 1/8, 16/96, 336/1728, 7296/34560,...

CROSSREFS

Sequence in context: A050893 A037025 A105063 * A274303 A132586 A208400

Adjacent sequences:  A166480 A166481 A166482 * A166484 A166485 A166486

KEYWORD

frac,nonn

AUTHOR

Daniel Tisdale, Oct 14 2009, Oct 16 2009

STATUS

approved

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Last modified April 19 08:26 EDT 2021. Contains 343110 sequences. (Running on oeis4.)