A107079 - OEIS

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A107079

Minimal number of squared primes in a squarefree gap of length n.

1, 2, 3, 4, 4, 5, 6, 7, 7, 7, 8, 9, 9, 10, 11, 12, 12, 13, 13, 14, 14, 15, 16, 17, 17, 17, 18, 18, 18, 19, 20, 21, 21, 22, 23, 24, 24, 25, 26, 27, 27, 28, 29, 30, 30, 30, 31, 32, 32, 32, 32, 33, 33, 34, 34, 35, 35, 36, 37, 38, 38, 39, 40, 40, 40, 41, 42, 43, 43, 44, 45, 46, 46, 47 (list; graph; refs; listen; history; internal format)

	OFFSET	`1,2`
	LINKS	`Louis Marmet, First occurrences of squarefree gaps and an algorithm for their computation` `Charles R Greathouse IV, Home Page [in lieu of email address]`
	FORMULA	`a(n)=sum{k=0..n-1, moebius_mu(n-k-1) mod 2}; a(n)=A013928(n+1)+A107078(n).`
	PROG	`(PARI) A107079(n)=1+sum(k=1, n-1, bitand(moebius(k), 1)) - Charles R Greathouse IV Sep 22 2008`
	CROSSREFS	`Cf. A045882.` `Sequence in context: A095769 A080820 A116549 * A025528 A123580 A072894` `Adjacent sequences: A107076 A107077 A107078 * A107080 A107081 A107082`
	KEYWORD	`nonn`
	AUTHOR	`Paul Barry (pbarry(AT)wit.ie), May 10 2005`
	EXTENSIONS	`New definition from Charles R Greathouse IV Sep 22 2008`

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Last modified February 15 08:12 EST 2012. Contains 205724 sequences.