A069016 Look at all the different ways to factorize n as a product of numbers bigger than 1, and for each factorization write down the sum of the factors; a(n) = number of different sums.
1, 1, 1, 1, 1, 2, 1, 2, 2, 2, 1, 3, 1, 2, 2, 3, 1, 4, 1, 3, 2, 2, 1, 5, 2, 2, 3, 3, 1, 5, 1, 4, 2, 2, 2, 7, 1, 2, 2, 5, 1, 5, 1, 3, 4, 2, 1, 8, 2, 4, 2, 3, 1, 7, 2, 5, 2, 2, 1, 9, 1, 2, 4, 6, 2, 5, 1, 3, 2, 5, 1, 10, 1, 2, 4, 3, 2, 5, 1, 8, 5, 2, 1, 8, 2, 2, 2, 5, 1, 10, 2, 3, 2, 2, 2, 12, 1, 4, 4, 7, 1, 5, 1
Offset: 1
Keywords
Examples
The factorizations of 12 are (2,2,3), (2,6), (3,4), and (12), which have three distinct sums 7, 8, and 12. Hence a(12) = 3. - _Antti Karttunen_, Oct 21 2017 The factorizations of 30 are (2,3,5), (2,15), (3,10), (5,6) and (30), which have the 5 distinct sums 10, 17, 13, 11 and 30. Hence a(30) = 5.
References
- Amarnath Murthy, Generalization of Partition Function and Introducing Smarandache Factor Partitions, Smarandache Notions Journal, Vol. 11, 1-2-3. Spring 2000.
Links
- Antti Karttunen, Table of n, a(n) for n = 1..10000
- Antti Karttunen, Scheme-program for computing this sequence
Formula
a(n) <= A001055(n). - David A. Corneth, Oct 21 2017
Extensions
Edited by David W. Wilson, May 27 2002
Edited by N. J. A. Sloane, Apr 28 2013