id:A074905 - OEIS Search Results

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Number of integers with an even number of distinct primes (for which mu(n)=1) between two consecutive primes p(n) and p(n+1).

+0
1

0, 0, 1, 1, 0, 2, 0, 2, 1, 0, 3, 2, 0, 1, 1, 3, 0, 2, 1, 0, 2, 1, 3, 4, 0, 0, 1, 0, 1, 5, 1, 2, 0, 5, 0, 1, 3, 1, 0, 2, 0, 3, 0, 1, 0, 7, 7, 1, 0, 0, 2, 0, 2, 2, 2, 2, 0, 1, 1, 0, 2, 7, 1, 0, 1, 7, 2, 3, 0, 0, 2, 2, 1, 1, 2, 1, 5, 1, 2, 4, 0, 2, 0, 1, 0, 3, 3, 1, 1, 1, 4, 3, 1, 2, 2, 1, 6, 0, 6, 4, 3, 2, 2, 1, 1 (list; graph; listen)

	OFFSET	`0,6`
	EXAMPLE	`Between 541 and 547 the 4 numbers which have an even number of distinct primes are as follows: {542,543,545,546}, so a(100)=4.`
	MAPLE	`readlib(issqr): sstmp := proc(n) local t1, i; t1 := 0; for i from ithprime(n) to ithprime(n+1) do if (issqrfree(i) = 'true' and mobius(i)=1) then t1 := t1+1; fi; od; t1; end: sstmp(200);`
	CROSSREFS	`Cf. A061265, A061399.` `Sequence in context: A127371 A036849 A097364 this_sequence A058548 A157030 A080844` `Adjacent sequences: A074902 A074903 A074904 this_sequence A074906 A074907 A074908`
	KEYWORD	`nonn`
	AUTHOR	`Jani Melik (jani_melik(AT)hotmail.com), Sep 30 2002`

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Last modified November 27 22:38 EST 2009. Contains 167602 sequences.

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