View Single Post
Old 2015-05-15, 07:40   #2
mshelikoff
 
mshelikoff's Avatar
 
"Marc Shelikoff"
Dec 2014
Cambridge, MA

3×5 Posts
Default Another Wolfram Alpha toy for unitary aliquot sequences

NestWhileList[Fold[#1 #2& , #[[1]]^#[[2]]+1& /@ Factor[#][[1]]]-#& , 1482, Unequal[##,1] && Unequal[##]&, {1,Infinity}]

can be used at Wolfram Alpha to generate the unitary aliquot sequence for the unitary sociable cycle starting with 1482. That messy code uses the formula for k=1 at http://mathworld.wolfram.com/Unitary...rFunction.html . I had to modify the mathematica code given at mathworld to meet the limitations of Wolfram Alpha. These aren't the aliquot sequences that folks in this forum usually play with. They're based on Sloane's A034448 at http://oeis.org/A034448 . Any lengthy computation leads to no results, and I have no idea if a different computation method would work faster, but Wolfram Alpha is popular among undergrads, so maybe it will see some use.

The widget toy with a Matrix Form wrapper and even terser code is at http://www.wolframalpha.com/widgets/...6831a652aa60f7 .
mshelikoff is offline   Reply With Quote