login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A045779 Number of factorizations of n into distinct factors for some n (image of A045778). 19
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, 40, 42, 43, 44, 46, 52, 54, 55, 56, 57, 59, 61, 64, 67, 70, 74, 76, 80, 83, 88, 89, 91, 93, 100, 104, 110, 111, 112, 116, 117, 120, 122, 123, 132, 137, 140, 141, 142, 143, 148 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

LINKS

Table of n, a(n) for n=1..66.

Wikipedia, Multiplicative partition

R. E. Canfield, P. Erdős and C. Pomerance, On a Problem of Oppenheim concerning "Factorisatio Numerorum", J. Number Theory 17 (1983), 1-28.

CROSSREFS

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

Strict factorizations are A045778 with image A045779 and complement A330975.

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

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

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

Sequence in context: A091402 A064817 A108549 * A235028 A062014 A164707

Adjacent sequences:  A045776 A045777 A045778 * A045780 A045781 A045782

KEYWORD

nonn

AUTHOR

David W. Wilson

EXTENSIONS

Name edited by Gus Wiseman, Jan 11 2020

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified September 25 12:38 EDT 2021. Contains 347654 sequences. (Running on oeis4.)