Math problem : III.7 Removing cards based on the rule

N sheets of card in which 1, 2, 3, ...., N is written each are clockwise arranged in the small order of the number circularly.

When removing one card at a time in accordance with the following rule, it is considered which card remains at the end.

<Rule 1>
The card in which 1 is written is removed first.

<Rule 2>
When a certain card is removed, the 2nd card from the card counted clockwise and will be removed.

This operation is repeated until only one card remains.

For example, in case of N = 13, cards are removed as shown in Fig. 1, and #10 card finally remains.
(x mark expresses the removed card.)



Answer the following questions.

(1) Answer the number written to the card which remains at the end in case of N = 8.

(2) When cards are removed at the 1st round in case of N = 16, as shown in Fig. 2, eight cards remain.

The card in which 2 was written is removed next.

Answer the number written to the card which remains at the end in case of N = 16.

Moreover, answer the number written to the card which remains at the end, respectively in case of N = 32 and N = 64.



(3) When the cards in which 1, 3, and 5 are written at the 1st round are removed in case of N = 35, 32 cards remain.

The card in which 7 was written is removed next.

Answer the number written to the card which remains at the end in case of N = 35.

(4) When 36 cards are removed to the 1st round in case of N = 100, 64 cards remain.

Answer the number written to the card which remains at the end in case of N = 100.

(5) Answer the number written to the card which remains at the end in case of N = 2009.












Answer
(1) 8 
(2) 16, 32, 64 
(3) 6 
(4) 72 
(5) 1970