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A222313 A222311 sorted and duplicates removed (conjectured). 3
1, 2, 3, 5, 6, 15, 17, 33, 41, 55, 57, 65, 70, 105, 129, 257, 273, 385, 561, 897, 969, 1001, 1105, 1353, 1430, 1785, 2049, 2145, 2337, 2665, 3553, 4097, 4305, 4745, 4845, 5633, 6105, 6545, 8193, 8385 (list; graph; refs; listen; history; text; internal format)
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

Table of n, a(n) for n=1..40.

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

Cf. A222310, A222311.

Sequence in context: A289124 A304297 A249752 * A079226 A055686 A126250

Adjacent sequences:  A222310 A222311 A222312 * A222314 A222315 A222316

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

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Last modified February 20 22:47 EST 2020. Contains 332086 sequences. (Running on oeis4.)