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,
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,
230400, 230700
090303
, n. : n, : 10 n = 1;
20 , n £ k (k ³ 1) n = k + 1.
, : (n) (1) , (k) (k + 1), .
1. .
. : ; ; ; . , . .
10. n = 1 .
20. , k ³1 n£ k . , n = k . . .
= = = ,
.
. ( ) , ( ). , - . , , Sn, S1, S2, S3, . , , , , () . , - . , 1, 3, 5, 7 , - .
, , , , , .. . .
2. , . , k = k + 1. 1 . k + 1 = k + 2, . n = 1.
3. 2n > 2n + 1 n ³ 3.
.
10. 23 > 7.
20. 2k + 1 = 2×2k > 2(2k + 1) = 4k + 2 = (2k + 3) + (2k 1) > 2k + 3.
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4. , n ³ 0 11n + 2 + 122n + 1 133.
.
10. 112 + 121 = 133 n = 0.
20. 11k +3 + 122(k + 1) +1 = 11×11k + 2 + 144×122k + 1 = (144133) ´ ´11k + 2 + 144×122k + 1 = 144 × (11k + 2 + 122k + 1) 133×11k + 2.
133 , 133. , 133.