login
The OEIS is supported by the many generous donors to the OEIS Foundation.

 

Logo
Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A174524 The total number of factors in unordered factorizations of A025487(n) (Least Prime signatures). 0
0, 1, 3, 3, 6, 8, 12, 17, 10, 20, 22, 34, 27, 35, 46, 61, 60, 54, 94, 75, 107, 37, 101, 123, 86, 170, 170, 176, 104, 207, 230, 128, 304, 356, 284, 242, 386, 217, 413, 192, 397, 506, 303, 434, 680, 442, 512, 698, 502, 703, 275, 847, 832, 151, 725, 818, 1244, 676, 993, 1190, 1079, 1162, 399, 1654, 1311, 446, 1572, 1501, 1207, 2158, 1007, 917, 1840, 1831, 1980, 2104, 1785, 1859, 1579, 556 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,3
COMMENTS
A025487(n) has a certain number of unordered factorizations with between 1 and A001222(A025487(n)) factors.
a(n) counts these factors that are >1. A025487(5) counts 8, 2*4, 2*2*2 with 1+2+3=6=a(5) factors, for example.
LINKS
FORMULA
a(n) = A066637(A025487(n)). [ _R. J. Mathar_, Oct 03 2010]
EXAMPLE
The table of factorizations in A162247 begins:
1
2
3
4 2 2
5
6 2 3
7
8 2 4 2 2 2
9 3 3
10 2 5
11
12 2 6 3 4 2 2 3
A025487(n) begins 1 2 4 6 8 12 ...
a(n) counts the elements larger than 1 in the A025487(n)-th row of A162247: 0 1 3 3 6 8 ...
CROSSREFS
Sequence in context: A241831 A239946 A130780 * A143592 A280197 A333526
KEYWORD
easy,nonn
AUTHOR
_Alford Arnold_, Mar 21 2010
EXTENSIONS
a(1) replaced by 0. Sequence extended - _R. J. Mathar_, Oct 03 2010
STATUS
approved

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

License Agreements, Terms of Use, Privacy Policy. .

Last modified March 4 23:31 EST 2024. Contains 370537 sequences. (Running on oeis4.)