In the sequence {an}, an = 43-3n, then when Sn takes the maximum value, n=______ ．

Let an = 43-3n ＞ 0, n ＜ 433 = 1413, ∵ A1 = 40 ＞ 0, so the sequence is negative from the 15th, the first 14 items are positive, and the maximum sum of the first 14 items is s 14 = (40 + 1) × 142 = 287

RELATED INFORMATIONS

1. How to simplify Sn = 4N + n (n-1) / 2 times 6 = 3N ^ 2 + n?
2. Proof of 1 / 2-1 / (n + 1) by the method of expansion and contraction
3. Prove. 1 + 1 / √ 2 + 1 / √ 3 +. + 1 / √ n
4. Given: (x + m) (x + n) = x ^ 2-6x + 8, then 2mn-3m-3n=
5. 1-9 / 41a ^ 3n-2 B ^ 2n + 3 is a binomial of degree six, and the value of n is obtained 2 if / M + 3 / + (n + 2) ^ 2 = 0, find the coefficients and times of (1) m, N; (2) the monomial MX ^ n + 4Y / 9
6. Let a = (COS (α + β), sin (α + β)), B = (COS (α - β), sin (α - β), and a + B = (4 / 5,3 / 5) find Tan α
7. Given that the vector a = (COS α, - 2) B = (- 1, sin α) and a ⊥ B, then Tan (2014 π - α)=
8. Vector a = (sin θ, 2), vector b = (COS θ, 1), vector a parallel, vector B, θ belong to (0, π / 2), (1) find Tan θ (2) Find sin θ and cos θ; (3) If sin (θ - φ) = 3 / 5,0
9. Given that vector a = (Tan α, 1) vector b = (2,1) and vector a ‖ vector B, then sin α · cos α Sin α = 2cos α is calculated
10. Given that the vector a = (COS θ, sin θ), the vector b = (3,1), and a ⊥ B, then the value of Tan θ is______ ．
11. The sum of the first n terms of the arithmetic sequence an is Sn = 3N ^ 2 + BN + C. If A3 = 17, what is A10
12. The sum of the first n terms of a sequence {an} is Sn = 2n ^ 2-3n, then A10 =?
13. Given that the nth power of a is 2 and the nth power of B is 3, then the 2nth power of a + the 3nth power of B
14. 4 to the power of n · a to the power of 2n · B to the power of 3N = () to the power of n
15. It is known that X and y are the two sides of a triangle, α, & szlig; are the two corners of the same triangle, and X, y, α, & szlig; satisfy the following relation xsin α + ycos & szlig; = 0 and xcos α - ysin & szlig; = 0, find the value of α, β
16. The positional relationship between xcos θ + ysin θ + a = 0 and xcos θ - ysin θ + B = 0 A. Parallel B. vertical C. oblique D. related to the value of a, B, θ D
17. The position relationship between the straight line xcos θ + ysin θ + a = 0 and the straight line xsin θ - ycos θ + B = 0 is site:219.226.9.43 What is the position relationship between the straight line xcos θ + ysin θ + a = 0 and the straight line xsin θ - ycos θ + B = 0?
18. The positional relationship between xcos θ + ysin θ + a = 0 and xsin θ - ycos θ + B = 0 is () A. Parallel B. vertical C. oblique D. related to the value of a, B, θ
19. What is the maximum distance from point a (1, - 3) to the line xsin β + ycos β = 2?
20. Xcos Ω / A + ysin Ω / b = 1, xsin Ω / a-ycos Ω / b = 1