On the rank equation of any normal division algebra
Alexa A. Albert · Bulletin of the American Mathematical Society · 1929
Raising each side of this equation to the power /' wherewe have Rummer's result for d = l, 2, • • • , (/ -3)/2.I think it highly probable that Kummer encountered this question in connection with a problem involving the second factor of the class number of k(Ç).I shall prove in another article that if the second factor of the class number is divisible by /, then (1) holds with not all the a's divisible by /.A somewhat similar result is proved by Hubert.*