The number of solutions is: 2,207,893,435,808,352
The nQueens problem consists in placing n queens on a nxn chessboard with that no queens are enable to capture each others.
Thanks to the ObjectWeb ProActive library, the computation was achieved in Peer-To-Peer mode (P2P), just using the spare CPU cycles of INRIA desktop machines. As such , the computing platform was highly heterogeneous: Linux, Windows, various JVMs, PII to Xeon bi-pro from 450 Mhz to 3.2 GHz, etc.
The total duration time was slightly over 6 months (4444h 54m 52s 854), starting October 8th until June 11th, using the spare CPU cycles of about 260 machines. The cumulated computing time was over 50 years: 53 years 2 days 16 hours 27 minutes 1 seconds 117 ms!