#83 Doubled squares
Set by Colin Beveridge
Can you find a three-digit square number that is 1 more than double a square number?
Can you find a four-digit square that is 1 more than double a square?
What is the smallest square that is 1 more than double a square that has a different number of digits?
Solution next week
#82 Flipping coins
Solution
Action #3 flips HH to TT in one move.
Yes, doing a pair of actions gives the same result whichever one is done first.
There are five ways to get from HH to TT without returning to a previous position: #1 then #2; #2 then #1; #1 then #3 then #1; #2 then #3 then #2; or #3.
Quick quiz #312
set by Corryn Wetzel
1 How many chambers does the human heart have?
2 Who holds the record for the longest single stay in space, at 437 days?
3 What tree produces the largest seeds in the world?
4 In what year did Rosalind Franklin capture "Photograph 51", pivotal to discovering DNA's structure?
5 What bacterium causes Lyme disease?
Quick quiz #312
Answers
1 Four
2 Valeri Polyakov
3 The coco de mer palm (Lodoicea maldivica)
4 1952
5 Borrelia burgdorferi