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A166721 For definition see Comments lines. 0
1, 4, 16, 36, 64, 144, 576, 900, 1024, 1296, 3600, 4096, 5184, 9216, 14400, 32400, 36864, 44100, 46656, 65536, 82944, 129600, 176400, 230400, 262144, 331776, 589824, 705600, 746496, 810000, 921600, 1166400, 1587600, 2073600, 2359296 (list; graph; refs; listen; history; internal format)
OFFSET

1,2

COMMENTS

Consider natural numbers N : 1, 2, 3, 4, 5, 6, 7, .... For these numbers, we introduce the definitions: Peace T - the set of all numbers N, in which the whole of T divisors (including 1 and the sheer number N); number of the world - the number (T) for any integer divisors of the number N of this world; odd world - a world with an odd number of T = 1, 3, 5, 7, ...; even the world - a world with even number of T = 2, 4, 6, 8, ...; leader of the world T - the number of N, whose first time (in the natural numbers), you are the type T;

top leaders of the odd worlds - the leaders (of N) of odd worlds, in which the number of T is monotonically increasing (in the natural numbers), starting with T = 1; even the worlds top leaders - the leaders (of N) of even the worlds in which the number of T is monotonically increasing (in the natural numbers), starting from T = 2. Given these definitions it is easy to find an infinite sequence leaders (N) odd worlds (with the odd T).

FORMULA

It appears that this sequence can not be described by the formula. (The rest of this line was illegible. - N. J. A. Sloane)

CROSSREFS

Also: A000005, A048691, A152674, A136404

Sequence in context: A016742 A121317 A063755 * A085040 A030179 A207025

Adjacent sequences:  A166718 A166719 A166720 * A166722 A166723 A166724

KEYWORD

easy,nonn,uned

AUTHOR

Alexander Isaev (i2357(AT)mail.ru), Oct 20 2009

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Last modified February 15 19:15 EST 2012. Contains 205852 sequences.