Bac 1: Tails cać tong
A = 1+ 2+ 3+ 4+
B = 1 + 3 + 5 +
C = 2 + 5 + 8 + 11 +
D = 1 + 5 + 9 +13
L
P
Q
=
2
sau i
2
...
+ ..
1 + 2 + 4 + 8 + 16 +
F = 1.2 + 2.3 + 3.4 +4.5 + --
G
1.3 + 3.5 +5.7 +...
H = 25 + 5.8 + 8.11 +...
I = 1.2.3 + 2.3.4 +3.4.5 +..
K = 2.4.6 + 4.6.8 + 6.8.10 + ...
= 2.5. ...
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