Copyright © University of Cambridge. All rights reserved.

## 'LOGO Challenge - Recollection' printed from http://nrich.maths.org/

Information processing on any real scale is best left to machines. The tedium of processing data is removed and the user can concentrate on testing intuitive thoughts and methods.

LOGO is a fine example of the machine freeing the end user to think and test out ideas and insights.

Below are several procedures for the reader to think about.

The invitation is to understand what is happening and explore the basic concept further.

TO BLOB :A :C

FD 10

RT :A

BLOB :A + :C :C

END

Try BLOB 10 36 and go from there.

TO HILBERT :A :LEV :RAT

IF :LEV = 0 [STOP]

LT 90 * :RAT

HILBERT :A :LEV - 1 :RAT * -1

FD :A

RT 90 * :RAT

HILBERT :A :LEV - 1 :RAT * 1

FD :A

HILBERT :A :LEV - 1 :RAT * 1

RT 90 * :RAT

FD :A

HILBERT :A :LEV - 1 :RAT * -1

LT 90 * :RAT

END

Try HILBERT 25 4 1 and begin researching from there.

##### Finally

TO SIERP :X :Y

REPEAT 4 [ FD :X LT 45 SIERPM :X :Y - 1 LT 45]

END

TO SIERPM :X :Y

SIERPN :X :Y RT 90 FD :X RT 90 SIERPN :X :Y

END

TO SIERPN :X :Y

IF :Y = 0 [ FD :X STOP]

SIERPN :X :Y - 1 LT 45 FD :X LT 45 SIERPM :X :Y - 1 LT 45 FD :X LT 45 SIERPN :X :Y - 1

END

Try SIERPN 20 4 andSIERPM 20

There is a lot of data here and it needs thoughtful exploring if some sense is to be made of it.

These programs were written using MSWLogo and you can download this excellent free software from the internet atÂ http://fmslogo.sourceforge.net/.