Slick Sammy stopped by the office and said to me, "David, did you know that this week is the only week in 2014 that the days are ordered forward as well as reverse?" I thought about it and realized Sammy was right. The day was 4/14/14, and when reversed it is identical. Sammy was a little off though, in that the numeric palindrome actually runs from 4/10/14 to 4/19/14. Coincidentally, there is one other day that is a numeric palindrome in April. Do you know what it is?

Sammy then pulled a calendar out of his pocket and said, "Let me show you something," and threw the calendar on my desk. "Open the calendar to any month and circle three consecutive days." I did as Sammy requested and circled three dates in a row on the calendar. "Next," he said, "I want you to add those three numbers together. For example, if you circled 5,6 and 7, you would add them together to obtain 18."It took me a minute to add them together. I said, "Sammy, my answer is 48." Without missing a beat, Sammy responded, "The days you circled are 15, 16 and 17." I answered, "That was pretty cool. " He said, "I'm not done yet. Now turn to another month and I want you to circle a two-by-two square of numbers."Again, I did as he requested and circled a square of numbers during the month of May. "Now what, Sammy?" He said, "OK, total the numbers in your square and tell me the total." I did as he requested and I said, "Sammy, the total this time around is 104." Almost immediately, Sammy said, "Hmm. This is a little trickier but I think you circled the following numbers: 29, 30, 22 and 23." I looked at my square, and sure enough, there were the 22nd, 23rd, 29th and 30th circled in a square."Those are a couple of pretty neat tricks, Sammy," I said. "Of course, I'm curious as to how they work.""I figured you would be," said Sammy. He smiled broadly and said, "Since it is spring and the weather is beautiful, I'm in a generous mood. Just this once I am going to explain these little tricks to you.""But first, one last effect. I want you to select a month and write it down." I wrote down the month of July. He took the piece of paper from me and wrote something on it, then crumpled it in a ball and placed it on my desk. "Now, I want you to turn to the month of July and add up all of the, hmm, let's try Tuesdays."I said, "The answer is 75." He told me to open the paper and there next to the July I wrote, he added a 75."Cool," I said. "Now are you going to show me?" "Yes," he answered. "First let's talk about the three numbers trick. The answer is basically some simple algebra, but since that fancy word scares folks, let's just call it some cool math." He continued, "All you need to do is ask the person to circle any three consecutive dates, then add up the numbers they circled and give you the total."I circled 3, 4 and 5. "The total is 12 in this case," I said. Sammy said, "All I do is take your total, which in this case is 12, and divide it by three." "That leaves a 4," I said, then the light clicked."Oh, I see. If I add one to 4, I will have a five, and if I subtract one from four I will have a three.""That's right," said Sammy. "All you do is divide by three and then add and subtract one to get your three digits.""OK, but what about that calendar trick with the square?" I asked. "Almost as easy," he answered. "Circle four numbers. I circled the 15, 16, 22 and 23." "Add the numbers up," he said,"and tell me the total." "The total is 76." Once again he correctly named the numbers."All you do this time," he said, "is divide the total by four and subtract four." Doing the math I found that 76 divided by 4 was simply 19. Subtracting four from nineteen yields 15, and that is the first number in the upper left corner of your square. Next I add one to get the next number, then I add 7 to get the number beneath it, and finally the last number is obtained by adding an eight to your number. I checked and 15 plus one was 16, 15 plus 7 was 22 and 15 plus 8 was 23. Sure enough that was the square."Now I understand these, but what about the last trick," I asked. He answered, "That is the easiest one of all. Look at my pad." I noticed on the third or fourth page groups of letters, JWd, FSt, MSt, ATu, MTh, JSu, JTu, AFr, SMo, OWe, NSa, DMo. I realized the first letters were months while the second letters were days of the week. "When you tell me what the month is, I give you a piece of paper to write it down. "I glance at the chart. You said, 'July.' I took the paper and wrote a 75 on it then crumpled it up. So I told you to add up the column that is headed by the one. The code tells me which column to ask you to add. In this case, add the Tuesdays.The total will always be 75 save February. If someone selects that month, unless it is a leap year, which works, I tell them that is too easy as there aren't as many days, so pick a more challenging month." He said once they pick the month and add the column, you end by revealing the total you wrote ahead of time.As he was leaving, Sammy said, "Enjoy, and by the way, your other numeric calendar palindrome is 4/1/14. Have a calendarific day."Till next time …