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A192719
Chain of Collatz sequences.
6
1, 2, 1, 3, 10, 5, 16, 8, 4, 2, 1, 6, 3, 10, 5, 16, 8, 4, 2, 1, 7, 22, 11, 34, 17, 52, 26, 13, 40, 20, 10, 5, 16, 8, 4, 2, 1, 9, 28, 14, 7, 22, 11, 34, 17, 52, 26, 13, 40, 20, 10, 5, 16, 8, 4, 2, 1, 12, 6, 3, 10, 5, 16, 8, 4, 2, 1
OFFSET
1,2
COMMENTS
The sequence is a chain of Collatz sequences. The first Collatz sequence in the chain is (1). Each of the subsequent Collatz sequences in the chain starts with the minimum positive integer that does not appear in the previous Collatz sequences. If the Collatz conjecture is true, then each Collatz sequence in the chain will end with 1, and the chain will include an infinite number of distinct Collatz sequences. If the Collatz conjecture is false, then the chain will end with the first Collatz sequence that does not converge to 1.
T(n,1) = A177729(n). - Reinhard Zumkeller, Jan 03 2013
EXAMPLE
The first Collatz sequence in the chain is (1). The second Collatz sequence in the chain is (2, 1), which starts with 2, since 2 is the smallest positive integer that doesn't appear the first Collatz sequence. The third Collatz sequence in the chain is (3, 10, 5, 16, 8, 4, 2, 1), which starts with 3, since 3 is the smallest positive integer that doesn't appear the previous Collatz sequences.
Thus this irregular array starts:
1;
2, 1;
3, 10, 5, 16, 8, 4, 2, 1;
6, 3, 10, 5, 16, 8, 4, 2, 1;
7, 22, 11, 34, 17, 52, 26, 13, 40, 20, 10, 5, 16, 8, 4, 2, 1;
9, 28, 14, 7, 22, 11, 34, 17, 52, 26, 13, 40, 20, 10, 5, 16, 8, 4, 2, 1;
...
PROG
(Java) See Lyons link.
(Haskell)
a192719 n k = a192719_tabf !! (n-1) !! (k-1)
a192719_row n = a192719_tabf !! (n-1)
a192719_tabf = f [1..] where
f (x:xs) = (a070165_row x) : f (del xs $ a220237_row x)
del us [] = us
del us'@(u:us) vs'@(v:vs) | u > v = del us' vs
| u < v = u : del us vs'
| otherwise = del us vs
-- Reinhard Zumkeller, Jan 03 2013
CROSSREFS
Cf. A220263 (row lengths); A070165, A220237.
Sequence in context: A260758 A091858 A070165 * A270996 A366325 A203709
KEYWORD
nonn,easy,tabf
AUTHOR
Robert C. Lyons, Dec 31 2012
STATUS
approved