双语畅销书《艾伦图灵传》第9章:退隐山林(57)
In 1876 the French mathematician E. Lucas proved that there was a way to decide whether 2p—1 was prime by a process of p operations of squaring and taking of remainders.
He announced that 2127—1 was prime. In 1937, the American D.H. Lehmer attacked 2257—1 on a desk calculator and after a couple of years of work showed that Mersenne had been mistaken.
并证明了2127-1是素数。1937年，美国的D·H·莱默利用台式计算器证明了2257-1是素数。接下来几年的工作表明，梅森的猜想是错误的，In 1949 Lucas's number was still the largest known prime.
直到1949年，卢卡斯的素数依然是人们所知的最大素数。
Lucas's method was tailor-made for a computer using binary numbers.
卢卡斯的方法是专门为二进制计算机设计的，They had only to chop up the huge numbers being squared into 40-digit sections and to program all the carrying.
所以他们需要做的工作，只是把大数分割成40位的小块，以便于存储。Newman explained the problem to Tootill and Kilburn and in June 1949 they managed to pack a program into the four cathode ray tubes and still leave enough space for working up to P = 353.
纽曼给托蒂尔和吉尔博解释了这个问题，并且在1949年6月，他们成功地做到，在加载了程序之后，仍有足够的空间来处理p小于353时的所有情形。En route they checked all that Euler and Lucas and Lehmer had done, but did not discover any more primes.
他们检查了欧拉、卢卡斯和莱默的所有工作，但却没能找到更大的素数注。This was part of an uneasy treaty of alliance, according to which the zones of 'engineers' and 'mathematicians' were agreed.
这不是一个简单的合作，是"工程师"和"数学家"之间的妥协。Newman took little further interest in the machine, and Alan took on the role of 'the mathematician'.
纽曼对这台机器已经不怎么感兴趣了，图灵接替了"数学家"的角色。It was for him to specify the range of operations that should be performed by the machine, although his list was in fact cut back by the engineers.
现在可以由他来指定，用什么操作来展示这台机器，尽管他提出的列表，已经被工程师们删减了不少。He had no part in the internal logical design, which was done by Geoff Tootill, but had control over the input and output mechanism, which lay more in the province of the user.
图灵在内部逻辑设计方面没有任何话语权，这些都由托蒂尔负责，他负责的是输入和输出机制，这与机器的使用者更直接相关。At the NPL he had chosen punched cards for input since they already had a punched card section; here he preferred to generate a teleprinter tape which could later be run off on a printer.
在国家物理实验室，因为他们有一个打孔卡片部门，所以图灵就选择用打孔卡片进行输入。而在这里，他则更喜欢产生一条电传纸带，这样就可以把它放进电传打字机。
