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A153078 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 = 2*3*5*7*11*13*17*19*23*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 November 27 22:38 EST 2009. Contains 167602 sequences.


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