colonel@sunybcs.UUCP (03/14/87)
Here's how Professor Fordney (remember him?) explained it to his class in 1933. (I've used this method since I read it!) To find the day of the week for any given date after 1752 do the following: 1. Take the last two figures of the year, add 1/4 of them, neglecting remainder. 2. Add for month, if for January or October, the numeral 1; May, 2; August, 3; February, March or November, 4; June, 5; September or December, 6; April or July, 0; if leap year [that is, if it is divisible by 4 without remainder] January 0, February 3. 3. Add day of month. Divide the sum of these three by 7 and remainder gives the number of the day of the week. Thus: _What day of the week was August 28, 1911?_ [1] 11 + 2 = 13 \ 44 = 7 x 6 + 2 or second day of week = | Monday. This applies only to the 20th [2] August = 3 > century. For 19th century, add 2; for | 21st century, add 6; 18th century, 4. [3] Date = 28 / --H. A. Ripley, "Tough Tim's New Year's Eve Party," in _How Good A Detective Are You_ (Lippincott, 1934) -- Col. G. L. Sicherman UU: ...{rocksvax|decvax}!sunybcs!colonel CS: colonel@buffalo-cs BI: colonel@sunybcs, csdsiche@ubvms