At 05:00 PM 8/20/2005, David Wilson wrote: >n a(n) >1 1 >2 422 >3 174 >5 22830 >6 <=1292013541080148674 >7 234374 This is now sequence A109473, and a(13) = 8678016978774. a(6) and a(11) are already in the on-line sequence. a(10) is the first unknown term and will be difficult to find.