Page "Mersenne prime" Paragraph 26

The search for Mersenne primes was revolutionized by the introduction of the electronic digital computer.

Alan Turing searched for them on the Manchester Mark 1 in 1949, but the first successful identification of a Mersenne prime, M < sub > 521 </ sub >, by this means was achieved at 10: 00 P. M. on January 30, 1952 using the U. S. National Bureau of Standards Western Automatic Computer ( SWAC ) at the Institute for Numerical Analysis at the University of California, Los Angeles, under the direction of Lehmer, with a computer search program written and run by Prof. R. M.

Robinson.

It was the first Mersenne prime to be identified in thirty-eight years ; the next one, M < sub > 607 </ sub >, was found by the computer a little less than two hours later.

Three more — M < sub > 1279 </ sub >, M < sub > 2203 </ sub >, M < sub > 2281 </ sub > — were found by the same program in the next several months.

M < sub > 4253 </ sub > is the first Mersenne prime that is titanic, M < sub > 44497 </ sub > is the first gigantic, and M < sub > 6, 972, 593 </ sub > was the first megaprime to be discovered, being a prime with at least 1, 000, 000 digits.

All three were the first known prime of any kind of that size.