x = 39, y = 23, rule = B3678/S34678
19bo$$19bo$$19bo$11bo15bo$19bo$11bo15bo$8boo3boo4bo4boo3boo$3b5obb3obb
4ob4obb3obb5o$b10ob15ob10o$b18ob18o$11ob15ob11o$oob5obb3obb4ob4obb3obb
5oboo$8boo3boo4bo4boo3boo$11bo15bo$19bo$11bo15bo$19bo$$19bo$$19bo!
A period 50 spark oscillator.
The central spark can become a two bit spark if the column is duplicated.
David I. Bell, May 1997
