www.youtube.com/watch?v=gvN6OwqFMuUwww.youtube.com/watch?v=t6xEl_7t8TMTwo episodes of "Think of a Number" here, one is a bit seasonal....
""Missing or incomplete episodes for programme THINK OF A NUMBER.
02.04.77 [pilot] (existence unknown)
Series 1
12.04.78 Episode 1 (existence unknown)
19.04.78 Episode 2 (existence unknown)
26.04.78 Episode 3 (existence unknown)
03.05.78 Episode 4 (existence unknown)
10.05.78 Episode 5 (existence unknown)
17.05.78 Episode 6 (existence unknown)
Series 2
12.09.79 The Pressure's Mine (existence unknown)
19.09.79 Absolutely Nothing (existence unknown)
26.09.79 Face Facts (existence unknown)
03.10.79 Seeing The Light (existence unknown)
10.10.79 Mechanical Minds (existence unknown)
17.10.79 Getting Things Moving (existence unknown)
Series 3
10.09.80 Wheels Within Wheels (existence unknown)
17.09.80 The Science Of See-Through Sand (existence unknown)
24.09.80 No Cockles, Just Muscles, Alive Alive Oh (existence unknown)
01.10.80 Elementarianisticalizationableism (existence unknown)
08.10.80 Hello Listeners (existence unknown)
15.10.80 2D Or Not 2D, That Is The Question (existence unknown)
Series 4
15.09.82 Reproduction (existence unknown)
22.09.82 What Does Exactly Mean Exactly? (existence unknown)
29.09.82 Musical Numbers (existence unknown)
06.10.82 Box Clever (existence unknown)
13.10.82 Dangerous Curves (existence unknown)
20.10.82 Just By Chance (existence unknown)
Series 5
04.01.84 In The Balance (existence unknown)
11.01.84 Bounce And Stretch (existence unknown)
18.01.84 Plain Planes And Flights Of Fancy (existence unknown)
25.01.84 The Maze Of Ways From A To B (existence unknown)
01.02.84 Say It With Numbers (existence unknown)
08.02.84 Think Of A Number And Beat It! (existence unknown)
Series 6
26.09.84 The Four Side Saga (existence unknown)
03.10.84 Suck And Blow (existence unknown)
10.10.84 Let The Angle Of Force Be With You (existence unknown)
17.10.84 Up And Over (existence unknown)
24.10.84 All Star Think Of A Number Show (existence unknown)
31.10.84 All Action Body Show (existence unknown)
All 37 episodes are missing.""