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A045779 Number of factorizations of n into distinct factors for some n (image of A045778). 19

%I #17 Jan 11 2020 20:48:36

%S 1,2,3,4,5,6,7,8,9,10,12,14,15,16,17,18,19,21,22,25,27,31,32,33,34,38,

%T 40,42,43,44,46,52,54,55,56,57,59,61,64,67,70,74,76,80,83,88,89,91,93,

%U 100,104,110,111,112,116,117,120,122,123,132,137,140,141,142,143,148

%N Number of factorizations of n into distinct factors for some n (image of A045778).

%H Wikipedia, <a href="https://en.wikipedia.org/wiki/Multiplicative_partition">Multiplicative partition</a>

%H R. E. Canfield, P. Erdős and C. Pomerance, <a href="http://math.dartmouth.edu/~carlp/PDF/paper39.pdf">On a Problem of Oppenheim concerning "Factorisatio Numerorum"</a>, J. Number Theory 17 (1983), 1-28.

%Y Factorizations are A001055, with image A045782, with complement A330976.

%Y Strict factorizations are A045778 with image A045779 and complement A330975.

%Y The least number with A045779(n) strict factorizations is A045780(n).

%Y The least number with n strict factorizations is A330974(n).

%Y Cf. A001222, A033833, A045783, A318286, A328966, A330972, A330973, A330997.

%K nonn

%O 1,2

%A _David W. Wilson_

%E Name edited by _Gus Wiseman_, Jan 11 2020

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Last modified April 19 15:34 EDT 2024. Contains 371794 sequences. (Running on oeis4.)