‘A Fibonacci parkrun at Edinburgh‘

parkrun has spawned several unofficial and often relatively obscure ‘challenges’ over the years. .’Groundhog Day’ - finish with the same time at the same location on two consecutive parkruns, ‘Alphabeteer’ - attend a parkrun starting with every letter of the alphabet except x,  ‘Date Bingo’ - attend a parkrun on every day of the year, ‘Pirates!’ - run seven Cs and an R (say it out loud!). for example.

One of the most obscure challenges is the Fibonacci challenge - to attend a parkrun whose event number matches the first 14 of the Fibonacci sequence, in which each number is the sum of the two preceding ones. (These are 1, 2, 3, 5, 8, 13, 21, 34, 55, 89, 144, 233, 377, 610).

Today's Edinburgh parkrun was event number 610 - the last of the 14 numbers in the challenge. 

The sequence originates in Indian mathematics over 2000 years ago and was brought to Europe by the Italian mathematician Leonardo of Pisa, later known as Fibonacci, who introduced it to Western European mathematics at the beginning of the 13th century. 

The sequence and the golden ratio have broad applications, including in Nature, seashells, (see extra) petals, and even spiral galaxies!

I've not been much involved in any of these challenges, apart from the straightforward ones of the total number of parkruns completed (only six to go now to 500!) and the number of countries in which I have done a parkrun. Still, when I discovered that I already had - quite accidentally - already done thirteen of the 14 and that I only needed event number of 610 to complete the Fibonacci challenge myself, I decided that I would run (super slowly today because I was still recovering from the rather nasty cold I've had all week).

The Challenge attracted more participants than usual; no doubt many people were chasing the magic number - up by around a half, not to 610 but to nearer 650!