Boole (tree) the largest in Converse Basin Grove, was named around 1895 by A.H. Sweeny, a Fresno doctor, after Franklin A. Boole, a supervisor of the logging operation who spared the tree's life due to its great size. Before 1931, it was thought by many to be the largest tree in the world (although the General Grant Tree was more popularly known as the largest tree in the world at that time), but it is now known as the sixth largest tree, after five other giant sequoias: the General Sherman tree, the General Grant, the President tree, the Lincoln tree, and the
Largest known prime number the progression of the largest known prime number in ascending order. Here M = 2 − 1 is the Mersenne number with exponent "n". The longest record-holder known was M = 524,287, which was the largest known prime for 144 years. No records are known before 1456. GIMPS found the fourteen latest records (all of them Mersenne primes) on ordinary computers operated by participants around the world. A list of the 5,000 largest known primes is maintained by Chris K. Caldwell, of which the twenty largest are listed below. Largest known prime number The largest known prime number () is