

A220237


Triangle read by rows: sorted terms of Collatz trajectories.


6



1, 1, 2, 1, 2, 3, 4, 5, 8, 10, 16, 1, 2, 4, 1, 2, 4, 5, 8, 16, 1, 2, 3, 4, 5, 6, 8, 10, 16, 1, 2, 4, 5, 7, 8, 10, 11, 13, 16, 17, 20, 22, 26, 34, 40, 52, 1, 2, 4, 8, 1, 2, 4, 5, 7, 8, 9, 10, 11, 13, 14, 16, 17, 20, 22, 26, 28, 34, 40, 52, 1, 2, 4, 5, 8, 10, 16
(list;
graph;
refs;
listen;
history;
text;
internal format)



OFFSET

1,3


COMMENTS

T(n,1) = 1 if Collatz conjecture is true.


LINKS



EXAMPLE

The table begins:
. 1: [1]
. 2: [1,2]
. 3: [1,2,3,4,5,8,10,16]
. 4: [1,2,4]
. 5: [1,2,4,5,8,16]
. 6: [1,2,3,4,5,6,8,10,16]
. 7: [1,2,4,5,7,8,10,11,13,16,17,20,22,26,34,40,52]
. 8: [1,2,4,8]
. 9: [1,2,4,5,7,8,9,10,11,13,14,16,17,20,22,26,28,34,40,52]
. 10: [1,2,4,5,8,10,16]
. 11: [1,2,4,5,8,10,11,13,16,17,20,26,34,40,52]
. 12: [1,2,3,4,5,6,8,10,12,16] .


MAPLE

T:= proc(n) option remember; `if`(n=1, 1,
sort([n, T(`if`(n::even, n/2, 3*n+1))])[])
end:


MATHEMATICA

Flatten[Table[Sort[NestWhileList[If[EvenQ[#], #/2, 3#+1]&, n, #>1&]], {n, 12}]] (* Harvey P. Dale, Jan 28 2013 *)


PROG

(Haskell)
import Data.List (sort)
a220237 n k = a220237_tabf !! (n1) !! (k1)
a220237_row n = a220237_tabf !! (n1)
a220237_tabf = map sort a070165_tabf


CROSSREFS



KEYWORD



AUTHOR



STATUS

approved



