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A101367 Perfect Abs. Real part of complex z such that Abs[(Total[Divisors[z]]-z)]=Abs[z]. 4
5, 3, 19, 15, 29, 6, 74, 19, 111, 147, 185, 91, 197, 269, 122, 159, 72, 827, 1487, 2903, 968, 999, 702, 5803, 326, 2474, 7871 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,1
COMMENTS
Having Perfect Abs is not as good as being Perfect. A complex number can also have Abundant Abs or Deficient Abs.
LINKS
EXAMPLE
The divisors for 269+92i are: 1, 2+I, 3+4i, 6+5i, 7+2i, 7+16i, 12+11i, 13+34i, 17+126i, 32+47i, 39+2i, 269+92i. The (sum - k) is 139+248i. Abs[139+248i] == Abs[269+92i]
MATHEMATICA
Re[Sort[Select[Flatten[Table[a + b I, {a, 1, 500}, {b, 1, 500}]], Abs[Total[Divisors[ # ]] - # ] == Abs[ # ] &], Abs[ #1] < Abs[ #2] &]
CROSSREFS
Sequence in context: A073845 A169697 A092525 * A338790 A256565 A298098
KEYWORD
nonn
AUTHOR
Ed Pegg Jr, Jan 13 2005
EXTENSIONS
Ten more terms from Hans Havermann, Jan 15 2005
STATUS
approved

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Last modified May 21 07:02 EDT 2024. Contains 372729 sequences. (Running on oeis4.)