1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 37 39 41 …… 其中,第N行的第三个数字的通式是什么?1 3 5 7 9 1113 15 17 1921 23 25 27 2931 33 37 39 41……其中,第N行的第三个数字的通式是什么?

1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 37 39 41 …… 其中,第N行的第三个数字的通式是什么?1 3 5 7 9 1113 15 17 1921 23 25 27 2931 33 37 39 41……其中,第N行的第三个数字的通式是什么?
1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 37 39 41 …… 其中,第N行的第三个数字的通式是什么?
1
3 5
7 9 11
13 15 17 19
21 23 25 27 29
31 33 37 39 41
……
其中,第N行的第三个数字的通式是什么?

1 3 5 7 9 11 13 15 17 19 21 23 25 27 29 31 33 37 39 41 …… 其中,第N行的第三个数字的通式是什么?1 3 5 7 9 1113 15 17 1921 23 25 27 2931 33 37 39 41……其中,第N行的第三个数字的通式是什么?
设第N行的第一个数字是an
a(n+1)-a(n)=2n
an=(an-a(n-1))+(a(n-1)-a(n-2))+.+(a2-a1)+a1=2（n-1+n-2+.+1)+1=n(n-1)+1
第三个数是第一个加4
即n(n-1)+5 n>=3

N^2-N+5

我只想问，35怎么变成?了……

Hit the red man to hand covering her face.

the reporter Dai Shuwei correspondent temperature is the highest per photo coverage of any green today, Miss Dong people reported to the correspo...

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Hit the red man to hand covering her face.

the reporter Dai Shuwei correspondent temperature is the highest per photo coverage of any green today, Miss Dong people reported to the correspondent, April 22 at 10 am, she lived in the area of ??the elevator they face a red man trotter. When she loudly denounced each other, they were publicly beaten by men in red. Let her even more chilling is that the elevator men and women within the presence of other sixty-seven witnessed this scene, but no one dared to come forward to stop this, and some even deliberately turn on the head, pretended. Indignant, she pulled out a cell phone plan on the spot when an alarm, the phone is also red man brutally smashed to the ground. After extensive investigation, the police yesterday evening in Futian the man home and arrested him. Currently, the law suspects have been detained by the security police.
victim angry complaint: was Although things have passed two days, but when the parties brought the matter to Miss Dong is still very emotional.
22 evening 10 o'clock, Miss Dong from the outside back to the apartment. Waiting for the elevator, she found a flat red men followed in their own back. The elevator opened,tory burch sales, she walked in front, followed by red man entered the elevator, the elevator and pressed against the corner of her intention. Suddenly, she was red man forced his hand caught in a couple of her arm, she instinctively ducked. Unexpectedly, the other continued to crowd around her. Intolerable under Miss Dong directed at men, loud Hanliaoliangsheng . Miss Dong pick up the phone in the alarm ready when the elevator stopped. At this time, man has destroyed the hand phone in her hands, then sped away.
Miss Dong said the elevator and that was her name in addition to red man, there sixty-seven men and women, should also live here or tenant households, be neighbors. However, her chilling is that in the process, no one has come forward to stop this, even people will head torsional elsewhere, pretended. Only in the red man down the elevator, the elevator only to persuade a young man, she said,tory burch flip flops, Out of the elevator 10 minutes later, she called the police.
police investigation: a real assault, indecent assault yet to be determined

responsible for handling the case of the South Park Police Station Detective Inspector Chen Ying-chou, confirmed to reporters after the transfer of the scene monitoring video, red man assaulted the victim's circumstances is true. As the surveillance video can not be displayed on the red man, the woman whether the implementation of the
Chen detective said the man named to be 50 years or younger, from Zhejiang, in the deep unemployed, currently living in South Road Jia × × Apartment 7th floor of their homes earlier this year just for his own buy real estate.
After receiving the alarm, the leadership attaches great importance to the South Park police station, immediately sent the police to investigate the case. By looking at surveillance video and access to registration information officers, the police on the 24th at 6 pm in the downstairs residence red man and arrested him.
After a preliminary investigation, the man of their Miss Dong confessed to the assault, but the two sides dispute the cause of another argument. As the most direct evidence - on-site video surveillance point of view is unclear whether Miss Dong should have a Currently, should a security detention by the police.
man defense: physical contact,tory burch outlets, no sexual harassment

yesterday, in the police station should be a police investigation is still beating the day's dress: flat head, wearing a red T-shirt and jeans, medium height, more body fat. That reporters take pictures of a soon to be blocked up by hand to their face.
I hit her hand when I was in a fit of anger, so the cell phone in her hands again hit the ground. sexual harassment. He expressed the hope that reconciliation and Miss Dong, do not want to make things so much.
finished an interview with reporters to leave the police station, outside the police station, who claimed to be a He
(please writer who receive 100 yuan rebellion Award)

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35

[1+99]=100 10×5=50 50除2=25 25×100=2500