Unsolved Problems in Number Theory
Richard Guy
Bennett, Györy & Hajdu show that the product of consecutive members of a k-
term A.P. is not a power for 4 ~ k < 11, except in cases where there is a common
factor, as in 9. 18. 27.36 = 54°. In a 93-05-07 letter to Ron Graham, Nobuhisa Abe
...