Fill in the blanks in the first day of junior high school! 1×2=1／3×1×2×3,1×2+2×3=1／3×2×3×4,1×2+2×3+3×4+4×5 =1／3×4×5×6,... According to the above rule, please guess: 1 × 2 + 2 × 3 + 3 × 4 +... + n (n + 1) (n is an integer)=------------- Very urgent ah, help, the right answer plus 50 points ah, speed!

Fill in the blanks in the first day of junior high school! 1×2=1／3×1×2×3,1×2+2×3=1／3×2×3×4,1×2+2×3+3×4+4×5 =1／3×4×5×6,... According to the above rule, please guess: 1 × 2 + 2 × 3 + 3 × 4 +... + n (n + 1) (n is an integer)=------------- Very urgent ah, help, the right answer plus 50 points ah, speed!

1/3 * n(n+1)(n+2)
Is it too late?

Fill in the blanks
（1） 1,1,2,3,5,（ ）,（ ）,21,34.
(2) 1 / 3, 3 / 7, 5 / 11, (), (), ()
(3) 4,2,1,1 / 2,1 / 4, (), (), ()

Question 1: the sum of two adjacent numbers is equal to the next number, so fill in 8 and 13 respectively
In the second question, the denominator difference is 4 and the numerator difference is 2, so the three blanks are 7 out of 15, 9 out of 19 and 11 out of 23 respectively
Third, the number of adjacent phases is less than 1 / 2, so the three blanks are 1 / 8, 1 / 16 and 1 / 32 respectively,
See?
Please accept

In a column of numbers 2,7,14,23. What is the 14th number

1.2 +5 =7
2.7 +7 =14
3.14 +9 =23
4.23 +11 =34
5.34 +13=47
6.47 +15=62
7.62 +17=79
8.79 +19=98
9.98 +21=119
10.119+23=142
11.142+25=167
12.167+27=194
13.194+29=223
14.223+31=254
Arithmetic sequence