feakbeak said:A thread about numerical series and patterns... cool!
Here is one of my favorites.
1 + 3 = 4 (2^2)
1 + 3 + 5 = 9 (3^2)
1 + 3 + 5 + 7 = 16 (4^2)
In general, summing the first n odd numbers will always give you n^2. Very cool!
No, he's right. In your example, n=5, not 4, since you have 5 odd numbers, not 4.MOFS said:Actually isn't that (n+1)^2?! unless you count 1^2 = 1 as your first one?!
eg when n=4, it would be 1 + 3 + 5 +7 + 9 = 25 (5^2)
emw said:No, he's right. In your example, n=5, not 4, since you have 5 odd numbers, not 4.
It works even if n=1, since the first n odd numbers =1, summed =1, and equals 1^2.
Ah, yes. Thinking outside the box, I see!MOFS said:Actually, retrospectively, we're both right. In my case, n would be the number in the sequence ie 1) 1 + 3 = 2^2 (2) 1 + 3 + 5 = 3^2...(n) 1 + 3 + 5 +...+nth odd number = (nth odd number+1)^2. When n=9, the square is 100.
In your example, n=the number of odd numbers in the sequence ie when there are 9 numbers in the sequence n=9 and the square = 81.
More than one way to skin a cat! And cause maths confusion...
Doctor Q said:I find it interesting that most people are happy to write days and months with either one or two digits (05/05/05 or 5/5/05), but are so used to years with two digits that they are going to spend the whole decade writing the year as 05. Why not just 5? After all, you only need the zeroes if you are going to write 2005.
Maybe we could collect them all and sell them as breakfast cereal.Awimoway said:To think of all those wasteful zeroes through the years...
Doctor Q said:Maybe we could collect them all and sell them as breakfast cereal.
Awimoway said:I finally broke down this January (consider it a New Year's resolution), when the days and months went back to single digits, and began writing the year in single digit. So it took me half the decade to finally capitalize on this little productivity boost. To think of all those wasteful zeroes through the years...
Tragic.
I consider that to be the funniest post I've read in weeks.He probably counted from 7 to 12.
Thought you might appreciate this
I have to confess I noticed it tooWake up, ancient thread, wake up!
I hereby report that I celebrated the big moment yesterday when the date and time (in "sort" order) were 07 08 09 10:11:12.
I hope you all enjoyed it too!
You could also round it to post 3141593.continuing Dr. Q's Pi fetish, here's the pi thread