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A178168
Product of the numbers in the Collatz (3x+1) trajectory of n, including n.
4
1, 2, 153600, 8, 5120, 921600, 704889816350720000, 64, 2486851272085340160000, 51200, 4577206599680000, 11059200, 532480000, 9868457428910080000, 114523513552896000000000, 1024, 12238520320000, 44763322897536122880000
OFFSET
1,2
COMMENTS
Row n of A070165 has the Collatz trajectory of n. It appears that all products are unique. This has been verified for all n < 10^6 and for the 12332052 values of n for which a(n) < 2^1081.
EXAMPLE
The Collatz iteration starting with 3 is 3, 10, 5, 16, 8, 4, 2, 1. The product of these numbers is 153600.
MATHEMATICA
Collatz[n_] := NestWhileList[If[EvenQ[ # ], #/2, 3#+1] &, n, #>1 &]; Table[Times@@Collatz[n], {n, 100}]
CROSSREFS
Cf. A087226 (LCM of the trajectory), A178169, A178170
Sequence in context: A122540 A324438 A167518 * A271669 A006935 A070833
KEYWORD
nonn
AUTHOR
T. D. Noe, May 21 2010
STATUS
approved