A124033 - OEIS

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A124033

Number of n-digit numbers having exactly n prime factors (counted with multiplicity).

4, 31, 225, 1563, 10222, 63030, 374264, 2160300, 12196405, 67724342, 371233523, 2014305995 (list; graph; refs; listen; history; internal format)

	OFFSET	`1,1`
	COMMENTS	`Essentially the same as A036335.` `What would be the ratio between a(n) and all possible numbers with n digits for each n?`
	EXAMPLE	`a(1) = A006880(1) = 4.` `a(2) = A066265(2) - A066265(1) = 34 - 3 = 31.` `a(3) = A109251(3) - A109251(2) = 247 - 22 = 225.` `a(4) = A114106(4) - A114106(3) = 1712 - 149 = 1563.` `a(5) = A114453(5) - A114453(4) = 11185 - 963 = 10222.` `a(6) = A120047(6) - A120047(5) = 68963 - 5933 = 63030.` `a(7) = A120048(7) - A120048(6) = 409849 - 35585 = 374264.` `a(8) = A120049(8) - A120049(7) = 2367507 - 207207 = 2160300.` `a(9) = A120050(9) - A120050(8) = 13377156 - 1180751 = 12196405.` `a(10) = A120051(10) - A120051(9) = 74342563 - 6618221 = 67724342.` `a(11) = A120052(11) - A120052(10) = 407818620 - 36585097 = 371233523.` `a(12) = A120053(12) - A120053(11) = 2214357712 - 200051717 = 2014305995.`
	MATHEMATICA	`Table[Count[Range[10^(n-1), 10^n-1], _?(PrimeOmega[#]==n&)], {n, 8}] (* From Harvey P. Dale, Apr 22 2011 *)`
	CROSSREFS	`Sequence in context: A059938 A179562 A005216 * A014537 A136284 A183911` `Adjacent sequences: A124030 A124031 A124032 * A124034 A124035 A124036`
	KEYWORD	`nonn,base`
	AUTHOR	`J. M. Bergot (thekingfishb(AT)yahoo.ca), Apr 08 2011`
	EXTENSIONS	`Corrected and extended by Ray Chandler (rayjchandler(AT)sbcglobal.net), Apr 11 2011` `a(9)-a(12) from Ray Chandler (rayjchandler(AT)sbcglobal.net), Apr 12 2011`

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Last modified February 17 14:50 EST 2012. Contains 206050 sequences.