A087254 If we start the Collatz-iteration at these values, each divisible by 4, all subsequent terms in trajectory are smaller than the initial value.

4, 8, 20, 24, 32, 48, 56, 68, 72, 80, 84, 96, 104, 116, 128, 132, 144, 152, 168, 176, 180, 192, 200, 212, 224, 228, 240, 260, 264, 272, 276, 288, 296, 308, 312, 320, 324, 336, 344, 356, 360, 368, 372, 384, 392, 404, 408, 416, 452, 456, 464, 468, 480, 488, 512

Offset: 1

Author

Labos Elemer, Sep 08 2003

Keywords

• nonn

Comments

Numbers that are not highest in any Collatz trajectory other than n. - Jayanta Basu, May 27 2013

Examples

			n=104: iteration list = {104,52,26,13,40,20,10,5,16,8,4,2,1}, where initial-value = largest-term.
		

Crossrefs

Cf. A025586, A087251-A087253, A222562 (with 1 and 2 prepended).

Programs

Mathematica

mcoll[n_]:=Max@@NestWhileList[If[EvenQ[#],#/2,3#+1] &,n,#>1 &]; t={}; Do[c=i=0; While[c!=1 && ++iJayanta Basu, May 27 2013 *)