id:A128951 - OEIS Search Results

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a(n) is equal to the number of positive integers m less than or equal to 10^n such that m is not divisible by the prime 5 and is not divisible by at least one of the primes 2, 3 and 7.

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78, 781, 7809, 78096, 780952, 7809524, 78095238, 780952381, 7809523809, 78095238096, 780952380952, 7809523809524, 78095238095238, 780952380952381, 7809523809523809, 78095238095238096, 780952380952380952 (list; graph; listen)

	OFFSET	`2,1`
	LINKS	`Milan Janjic, Enumerative Formulas for Some Functions on Finite Sets`
	FORMULA	`f(n)= 10^n-floor(10^n/5)-floor(10^n/42)+floor(10^n/210)`
	EXAMPLE	`a(6)=780952`
	MAPLE	`f := n->10^n-floor(10^n/5)-floor(10^n/42)+floor(10^n/210);`
	CROSSREFS	`Cf. A092695.` `Sequence in context: A129238 A147619 A119093 this_sequence A114532 A027786 A036524` `Adjacent sequences: A128948 A128949 A128950 this_sequence A128952 A128953 A128954`
	KEYWORD	`nonn`
	AUTHOR	`Milan R. Janjic (agnus(AT)blic.net), Apr 28 2007`

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Last modified December 2 11:54 EST 2009. Contains 167921 sequences.

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