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 A185455 Trajectory of 7 under repeated application of the map in A185452. 4
 7, 18, 9, 23, 58, 29, 73, 183, 458, 229, 573, 1433, 3583, 8958, 4479, 11198, 5599, 13998, 6999, 17498, 8749, 21873, 54683, 136708, 68354, 34177, 85443, 213608, 106804, 53402, 26701, 66753, 166883, 417208, 208604, 104302, 52151, 130378, 65189, 162973, 407433, 1018583, 2546458, 1273229, 3183073, 7957683, 19894208, 9947104 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS It is conjectured that this trajectory is unbounded, but this is an open problem. REFERENCES J. C. Lagarias, ed., The Ultimate Challenge: The 3x+1 Problem, Amer. Math. Soc., 2010; see page 89. LINKS Rémy Sigrist, Table of n, a(n) for n = 1..10000 Index entries for sequences related to 3x+1 (or Collatz) problem MAPLE f:=n->if n mod 2 = 0 then n/2 else (5*n+1)/2; fi; T:=proc(n, M) global f; local t1, i; t1:=[n]; for i from 1 to M-1 do t1:=[op(t1), f(t1[nops(t1)])]; od: t1; end; T(7, 120); CROSSREFS Cf. A185452, A185453, A185454. Sequence in context: A113613 A070415 A034083 * A103570 A223247 A091832 Adjacent sequences: A185452 A185453 A185454 * A185456 A185457 A185458 KEYWORD nonn AUTHOR N. J. A. Sloane, Feb 04 2011 STATUS approved

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Last modified February 24 22:04 EST 2024. Contains 370307 sequences. (Running on oeis4.)