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!)
A086473 Numbers in A058080 having only one factor pair (both distinct from 1) that add up to a sum belonging to A014092. 3
18, 24, 28, 50, 52, 54, 76, 92, 96, 98, 100, 112, 124, 140, 144, 148, 152, 160, 172, 176, 188, 192, 208, 212, 216, 220, 228, 232, 242, 244, 260, 266, 268, 280, 288, 290, 292, 304, 308, 316, 332, 336, 338, 344, 356, 374, 384, 388, 392, 400, 412, 434, 436, 448 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
Related to the "Impossible Problem" of Martin Gardner.
REFERENCES
M. Criton, "Le Problème Impossible", Jeux Mathématiques, Tangente Hors Série No. 20 Pole Paris 2004.
LINKS
N. Hobson, Nick's Mathematical Miscellany, Two Logicians
Dr. Rob, The Math Forum, Two Mathematicians Problem
EXAMPLE
A058080(3)=18 is in the sequence because 18=2*9=3*6 and only 2+9=11 belongs to A014092. However, A058080(7)=30 is not in the sequence because 30=2*15=3*10=5*6 with both 2+15 and 5+6 belonging to A014092.
CROSSREFS
Sequence in context: A002505 A182438 A050772 * A271327 A243539 A076770
KEYWORD
nonn
AUTHOR
Lekraj Beedassy, Sep 09 2003
EXTENSIONS
Corrected and extended by Ray Chandler, Sep 21 2003
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 July 24 07:12 EDT 2024. Contains 374575 sequences. (Running on oeis4.)