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!)
A020697 Number of divisors of A019505(n). 3
1, 2, 3, 4, 6, 8, 10, 12, 16, 20, 24, 30, 36, 48, 60, 72, 84, 96, 120, 144, 168, 192, 224, 256, 320, 384, 448, 512, 576, 672, 768, 896, 1024, 1152, 1344, 1536, 1792, 2048, 2304, 2688, 3072, 3456, 4032, 4608, 5376, 6144, 6912, 8064, 9216, 10368, 11520, 12960, 14400, 17280 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,2
COMMENTS
Conjecture: all numbers of the form 3*2^n are in this sequence. - J. Lowell, Mar 12 2008 [This is false: 3*2^12 = 12288 is the smallest counterexample. - Klaus Brockhaus, Jul 24 2008]
LINKS
David A. Corneth, Table of n, a(n) for n = 1..172 (first 63 terms from J. Lowell)
FORMULA
a(n) = A000005(A019505(n)).
CROSSREFS
Sequence in context: A341016 A200678 A088881 * A175381 A369519 A213623
KEYWORD
nonn
AUTHOR
J. Lowell, May 11 2007, corrected Mar 20 2008
EXTENSIONS
More terms from Klaus Brockhaus, Jul 24 2008
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 28 05:02 EDT 2024. Contains 371235 sequences. (Running on oeis4.)