A220263 Lengths of Collatz trajectories starting with terms of A177729.

1, 2, 8, 9, 17, 20, 10, 18, 21, 21, 8, 11, 24, 112, 19, 27, 22, 22, 35, 9, 30, 17, 12, 25, 113, 113, 33, 20, 108, 28, 15, 23, 116, 15, 36, 36, 23, 10, 31, 18, 18, 13, 119, 26, 26, 39, 114, 114, 70, 34, 34, 21, 21, 47, 109, 47, 122, 29, 29, 42, 16, 16, 24

Offset: 1

Author

Reinhard Zumkeller, Jan 03 2013

Keywords

• nonn

Comments

Row lengths in A192719.

Links

• Reinhard Zumkeller, Table of n, a(n) for n = 1..10000

Crossrefs

Cf. A006577.

Programs

Haskell

a220263 = length . a192719_row

Mathematica

coll[n_]:=NestWhileList[If[EvenQ[#],#/2,3#+1]&,n,#>1&]; t={1}; Do[If[FreeQ[Union@@Table[coll[i],{i,n-1}],n],AppendTo[t,Length[coll[n]]]],{n,2,144}]; t (* Jayanta Basu, May 29 2013 *)