Spacefiller 1 is a spacefiller that was found by David Bell in September 1993. It was at one time the smallest known spacefiller, but it has since been surpassed by Max.
Its population in generation t is [(t+19)2+463]/4 if t = 0 (mod 4), [(t+19)2+487]/4 if t = 2 (mod 4), and [(t+18)2+639]/4 if t is odd. The top and bottom stretchers were created by Hartmut Holzwart, size optimization and the left and right stretchers were created by David Bell, and the original idea, middle part, and left/right stretcher connection were created by Alan Hensel.[1]
