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A220263
Lengths of Collatz trajectories starting with terms of A177729.
3
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
1,2
COMMENTS
Row lengths in A192719.
LINKS
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 *)
PROG
(Haskell)
a220263 = length . a192719_row
CROSSREFS
Cf. A006577.
Sequence in context: A004999 A105125 A230314 * A033492 A126160 A118962
KEYWORD
nonn
AUTHOR
Reinhard Zumkeller, Jan 03 2013
STATUS
approved