A004527 Ratios of successive terms are 1,2,2,3,4,4,5,6,6,...

1, 1, 2, 4, 12, 48, 192, 960, 5760, 34560, 241920, 1935360, 15482880, 139345920, 1393459200, 13934592000, 153280512000, 1839366144000, 22072393728000, 286941118464000, 4017175658496000, 56240459218944000

Offset: 0

Author

N. J. A. Sloane

Keywords

• nonn

Links

• Harvey P. Dale, Table of n, a(n) for n = 0..480

Programs

Mathematica

FoldList[Times,1,Flatten[Append[#,Last[#]]&/@Partition[Range[20],2]]] (* Harvey P. Dale, Oct 15 2011 *)