A049586 - OEIS

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A049586

GCD of cototients(A051953) of pairs of consecutive integers.

1, 1, 1, 1, 1, 1, 1, 1, 3, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 3, 3, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 5, 3, 1, 1, 1, 1, 3, 3, 1, 1, 1, 1, 1, 1, 1, 1, 3, 1, 1, 3, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 5, 1, 1, 1, 1, 3, 3, 1, 1, 3, 1, 1, 1, 1, 1, 1, 1, 3, 3, 1, 1, 1, 1, 1, 3, 1, 1, 1, 1, 1, 3 (list; graph; refs; listen; history; internal format)

	OFFSET	`0,9`
	FORMULA	`a(n) = GCD[w+1-Phi[w+1], w-Phi[w]] = GCD[A051953(w+1), A051953(w)] Most of the terms are 1.`
	EXAMPLE	`n = 9: a(9) = GCD[10-Phi(10), 9-Phi(9)] = GCD[6, 3] = 3. n = 10: a(10) = GCD[11-Phi(11), 10-Phi(10)] = GCD[1, 6] = 1`
	CROSSREFS	`Cf. A000010, A051953, A058515.` `Sequence in context: A030578 A030577 A070670 * A133721 A083202 A030560` `Adjacent sequences: A049583 A049584 A049585 * A049587 A049588 A049589`
	KEYWORD	`nonn`
	AUTHOR	`Labos E. (labos(AT)ana.sote.hu), Dec 28 2000`

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Last modified February 16 21:51 EST 2012. Contains 205978 sequences.