A178168 Product of the numbers in the Collatz (3x+1) trajectory of n, including n.

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.

Links

T. D. Noe, Table of n, a(n) for n=1..500

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

Adjacent sequences: A178165 A178166 A178167 * A178169 A178170 A178171

Keyword

nonn

Author

T. D. Noe, May 21 2010

Status

approved