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A256641 a(n) is the total number of free ends of 5 line segments expansion at n iterations (see Comments lines for definition). 5
5, 10, 10, 20, 40, 40, 20, 20, 40, 60, 70, 70, 100, 100, 40, 20, 40, 60, 80, 120 (list; graph; refs; listen; history; text; internal format)



The initial pattern consists of 5 straight line segments which are the radii of a regular pentagon. Their free ends are the ends of elements that do not contact or cross the other ones. Overlaps among different generations are prohibited except for one segment that connects between center points.

It appears that the sequence would be analog to 5*A032766 if the overlaps among different generations were prohibited without exception. See illustration in the links.

The terms of this sequence should be checked. - Omar E. Pol, Apr 13 2015


Table of n, a(n) for n=1..20.

Kival Ngaokrajang, Illustration of initial terms, 5*A032766


Cf. A032766, A222181.

Sequence in context: A226992 A201033 A242894 * A032242 A208541 A324593

Adjacent sequences:  A256638 A256639 A256640 * A256642 A256643 A256644




Kival Ngaokrajang, Apr 06 2015



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Last modified July 4 11:58 EDT 2020. Contains 335448 sequences. (Running on oeis4.)