The proof that Tetris is a win for the computer was published in Eureka 51 (1992) by Richard Tucker. (Someone else has posted a link to another paper proving th

The proof that Tetris is a win for the computer was published in Eureka 51 (1992) by Richard Tucker. (Someone else has posted a link to another paper proving this, but it's from 1997; Richard got there first.) The proof that Tris is a win for the player was published in Eureka 51 (1991) by Adam Chalcraft. Richard and Adam definitely know one another and I would be unsurprised to learn that they talked to one another about this stuff, but the actual writeups in Eureka were by different people. (Quite possibly a substantial amount of the thinking was done collectively at meetings of the "Puzzles and Games Ring", a sort of sub-organization of the Archimedeans (the student mathematical society at the University of Cambridge, which publishes Eureka).