January 31, 1986 On Page 39 Montgomery continued to find an amazing number of base 2 factors. Brent completely factored the second Mersenne number of which no factors were previously known. Suyama finished another Mersenne number. Smith and I factored a C61, McCurdy and Wunderlich factored the last C62 and Silverman finished the C63's and the small cofactors that Montgomery left. As a result of this work, at the bottom of page 39 the smallest composite number in Appendix C has 64 digits. There is a new champion for cfrac on Page 39; it is # 1692. (The second cfrac champion is # 1602.) Suyama notes that Brent's P21 divisor of 2,439-, discovered before the sequence numbers began, is a champion for p+1. For that P21, p+1 = 8.3.19.4673.13171.36037.121169 . Two corrections: Delete C75 2,263- from the initial segment of Ap- pendix C which was enclosed with Page 36. In the cover letter with Page 37 it should say that the full Appendix C contains 1955 composite numbers--not 1957 of them. These typos resulted from faulty editing of Appendix C in 1980. Keep the factors coming! Sam Wagstaff