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A045783 Least value with A045782(n) factorizations. 28

%I #11 Jan 11 2020 21:49:25

%S 1,4,8,12,16,24,36,60,48,128,72,96,120,256,180,144,192,216,420,240,

%T 1024,384,288,360,2048,432,480,900,768,840,576,1260,864,720,8192,960,

%U 1080,1152,4620,1800,3072,1680,1728,1920,1440,32768,2304,2592,6144

%N Least value with A045782(n) factorizations.

%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.

%e From _Gus Wiseman_, Jan 11 2020: (Start)

%e Factorizations of n = 1, 4, 8, 12, 16, 24, 36, 60, 48:

%e {} 4 8 12 16 24 36 60 48

%e 2*2 2*4 2*6 2*8 3*8 4*9 2*30 6*8

%e 2*2*2 3*4 4*4 4*6 6*6 3*20 2*24

%e 2*2*3 2*2*4 2*12 2*18 4*15 3*16

%e 2*2*2*2 2*2*6 3*12 5*12 4*12

%e 2*3*4 2*2*9 6*10 2*3*8

%e 2*2*2*3 2*3*6 2*5*6 2*4*6

%e 3*3*4 3*4*5 3*4*4

%e 2*2*3*3 2*2*15 2*2*12

%e 2*3*10 2*2*2*6

%e 2*2*3*5 2*2*3*4

%e 2*2*2*2*3

%e (End)

%Y All terms belong to A025487.

%Y The strict version is A045780.

%Y The sorted version is A330972.

%Y Includes all highly factorable numbers A033833.

%Y The least number with exactly n factorizations is A330973(n).

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

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

%Y Cf. A070175, A318284, A325238, A330974, A330989, A330992, A330998.

%K nonn

%O 1,2

%A _David W. Wilson_

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Last modified August 17 23:03 EDT 2024. Contains 375241 sequences. (Running on oeis4.)