The first differences for a sequence Un is the set of numbers Dn = Un+1 - Un They are the set of numbers obtained by subtracting the first number from the second, the second from the third, and so on.
First. It's UN-fold, as opposed to un-FOLD
in 1984
un in undo means... redo or to do it again
condalezza rice
Trygve Lie
1953
u. thant
Hilary Clinton.
Mailing Address: UN Headquarters First Avenue at 46th Street New York, NY 10017 USA
un manuel des premiers secours, un manuel de secourisme
Vijay Lakshmi Pandit