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Revision History for A045783 (Bold, blue-underlined text is an addition; faded, red-underlined text is a deletion.)

Showing entries 1-10 | older changes
Least value with A045782(n) factorizations.
(history; published version)
#11 by Susanna Cuyler at Sat Jan 11 21:49:25 EST 2020
STATUS

proposed

approved

#10 by Gus Wiseman at Sat Jan 11 20:49:33 EST 2020
STATUS

editing

proposed

#9 by Gus Wiseman at Sat Jan 11 20:48:38 EST 2020
CROSSREFS

The sorted version is A330972.

A permutation of A330972 (the sorted version)Includes all highly factorable numbers A033833.

Includes all highly factorable numbers (A033833).

Factorizations are A001055, with image A045782, with and complement A330976.

#8 by Gus Wiseman at Sat Jan 11 20:45:01 EST 2020
EXAMPLE

Factorizations of a(n) for n = 1, 4, 8, 12, 16, 24, 36, 60, 48:

#7 by Gus Wiseman at Sat Jan 11 16:50:58 EST 2020
LINKS

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

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.

EXAMPLE

From Gus Wiseman, Jan 11 2020: (Start)

Factorizations of a(n) for n = 1, 4, 8, 12, 16, 24, 36, 60, 48:

{} 4 8 12 16 24 36 60 48

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

2*2*2 3*4 4*4 4*6 6*6 3*20 2*24

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

2*2*2*2 2*2*6 3*12 5*12 4*12

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

2*2*2*3 2*3*6 2*5*6 2*4*6

3*3*4 3*4*5 3*4*4

2*2*3*3 2*2*15 2*2*12

2*3*10 2*2*2*6

2*2*3*5 2*2*3*4

2*2*2*2*3

(End)

#6 by Gus Wiseman at Sat Jan 11 16:45:52 EST 2020
CROSSREFS

All terms belong to A025487.

The strict version is A045780.

A permutation of A330972 (the sorted version).

Includes all highly factorable numbers (A033833).

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

Cf. Factorizations are A001055, with image A045782, with complement A330976.

Strict factorizations are A045778 with image A045779 and complement A330975.

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

STATUS

approved

editing

#5 by Russ Cox at Fri Mar 30 18:35:35 EDT 2012
AUTHOR

_David W. Wilson (davidwwilson(AT)comcast.net)_

Discussion
Fri Mar 30
18:35
OEIS Server: https://oeis.org/edit/global/202
#4 by N. J. A. Sloane at Sat Sep 13 03:00:00 EDT 2003
KEYWORD

nonn,new

nonn

AUTHOR

David W. Wilson (davidwwilson(AT)attbicomcast.comnet)

#3 by N. J. A. Sloane at Fri May 16 03:00:00 EDT 2003
KEYWORD

nonn,new

nonn

AUTHOR

dww

David W. Wilson (davidwwilson(AT)attbi.com)

#2 by N. J. A. Sloane at Mon May 08 03:00:00 EDT 2000
KEYWORD

nonn,new

nonn

AUTHOR

David Wilson (wilson@ctron.com)

dww