id:A153078 - OEIS Search Results

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Number of solutions for m such that sigma(m) = A002110(n) where A002110(n) is the product of the first n primes.

+0
3

0, 1, 1, 2, 2, 5, 2, 4, 5, 3, 7, 5, 10, 2, 8, 4, 5, 6, 11, 32, 42 (list; graph; listen)

	OFFSET	`1,4`
	FORMULA	`a(n) = A054973(A002110(n)). - Chandler`
	EXAMPLE	`a(10) = 3 because 2388809736, 3450503048 and 3696967556 are the only numbers with a sigma value = A002110(10). A002110(10) = 6469693230 = 23571113171923*29.`
	CROSSREFS	`Cf. A000203, A002110, A153076, A153077.` `Sequence in context: A061034 A111861 A004543 this_sequence A076200 A039931 A128645` `Adjacent sequences: A153075 A153076 A153077 this_sequence A153079 A153080 A153081`
	KEYWORD	`nonn,more`
	AUTHOR	`Donovan Johnson (donovan.johnson(AT)yahoo.com), Dec 19 2008`
	EXTENSIONS	`a(12)-a(21) from Ray Chandler (rayjchandler(AT)sbcglobal.net), Dec 28 2008`

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Last modified December 9 14:43 EST 2009. Contains 170430 sequences.