OFFSET
1,2
COMMENTS
Obtained by sorting and removing duplicates from the first 500 terms of A222311. There is no proof as yet that this list is complete up to 105. Only the first three terms shown are certain. Is there a proof that 4 cannot appear?
LINKS
Cristian Cobeli, Mihai Prunescu, Alexandru Zaharescu, A growth model based on the arithmetic Z-game, arXiv:1511.04315 [math.NT], 2015.
Cristian Cobeli, Alexandru Zaharescu, A game with divisors and absolute differences of exponents, arXiv:1411.1334 [math.NT], 2014 (see page 12).
MATHEMATICA
terms = 40; nmax0 = 5000;
seq[nmax_] := seq[nmax] = Union[Print[nmax]; Join[r = {1}, Table[Reverse[r = FoldList[#1*(#2/GCD[#1, #2]^2) & , n, r]], {n, 2, nmax}][[All, 1]]]][[1 ;; terms]];
seq[nmax = nmax0]; seq[nmax = 2 nmax]; While[seq[nmax] == seq[nmax/2], nmax = 2 nmax]; seq[nmax] (* Jean-François Alcover, Sep 04 2018, after Ivan Neretin in A222310 *)
CROSSREFS
KEYWORD
nonn,more
AUTHOR
N. J. A. Sloane, Feb 16 2013
EXTENSIONS
Corrected and extended using data from Cobeli et al., 2015. - N. J. A. Sloane, Aug 27 2016
More terms (computed from a list of 10000) from Jean-François Alcover, Sep 04 2018
STATUS
approved