A093708 - OEIS

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A093708

Number of odd nonprime differences of 2 (twin odd nonprimes) below 10^n.

0, 9, 200, 2748, 32041, 351174, 3729823, 38917403, 401729439, 4117307658, 41988266423, 426654761185, 4323703591195, 43725896820062, 441488068396967, 4451827503629449 (list; graph; refs; listen; history; internal format)

	OFFSET	`1,2`
	FORMULA	`Count twin odd nonprimes below 10^n` `a(n) = 10^n/2 - 2*A006880(n) + A007508(n) + 1 - Max Alekseyev (maxale(AT)gmail.com), May 11 2005`
	EXAMPLE	`a(2)=9 because under 100 there are 9 twin odd nonprimes, e.g. 27-25=2.`
	CROSSREFS	`Cf. A093683 A006880 A007508.` `Sequence in context: A196910 A064756 A197077 * A052145 A012061 A012168` `Adjacent sequences: A093705 A093706 A093707 * A093709 A093710 A093711`
	KEYWORD	`easy,nonn`
	AUTHOR	`Enoch Haga (Enokh(AT)comcast.net), Apr 10 2004`
	EXTENSIONS	`More terms from Max Alekseyev (maxale(AT)gmail.com), May 11 2005`

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Last modified February 17 06:27 EST 2012. Contains 205998 sequences.