A175668 - OEIS

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A175668

First differences of A175648.

4, 11, 1, 12, 1, 16, 7, 7, 17, 5, 4, 20, 4, 3, 1, 10, 12, 1, 13, 28, 18, 1, 3, 4, 4, 1, 1, 2, 32, 25, 13, 4, 4, 3, 1, 2, 4, 14, 4, 12, 23, 3, 16, 5, 9, 3, 9, 4, 4, 2, 34, 7, 15, 9, 3, 4, 4, 4, 4, 4, 10, 4, 14, 4, 5, 24, 17, 43, 7, 38, 14, 4, 9, 1, 4, 4, 10, 4, 28, 4, 14, 4, 14, 4, 4, 10, 4, 10 (list; graph; refs; listen; history; text; internal format)

	OFFSET	`1,1`
	COMMENTS	`Distance between twin semiprime pairs.`
	LINKS	`Table of n, a(n) for n=1..88.`
	MAPLE	`A175648 := proc(n) option remember; if n = 1 then 6; else for a from procname(n-1)+1 do if numtheory[bigomega](a) = 2 and numtheory[bigomega](a+4) = 2 then return a; end if; end do: end if; end proc:` `A175668 := proc(n) A175648(n+1)-A175648(n) ; end proc:` `seq(A175668(n), n=1..100) ; # R. J. Mathar, Aug 07 2010`
	CROSSREFS	`Cf. A053319, A175612, A175648.` `Sequence in context: A230024 A132150 A091389 * A113249 A087171 A282026` `Adjacent sequences: A175665 A175666 A175667 * A175669 A175670 A175671`
	KEYWORD	`nonn`
	AUTHOR	`Juri-Stepan Gerasimov, Aug 05 2010`
	EXTENSIONS	`Terms from a(33) on corrected by R. J. Mathar, Aug 07 2010`
	STATUS	`approved`

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Last modified April 16 17:01 EDT 2021. Contains 343050 sequences. (Running on oeis4.)