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A128127 The number of regular pentagons found by constructing points on each side of the pentagon such that these points divide each side into equally-sized segments (i.e. a midpoint each side or 2 points on each side placed to divide each side into 3 equally-sized segments or so on), do the same construction for every side of the pentagon so that each side is equally divided in the same way. Connect all such points to each other with lines that are parallel to at least 1 side of the polygon. With 1 points, there is only 1 pentagon. With 1 point (a midpoint on each side), 3 regular pentagons are found. With two points, 9 regular pentagons are found in total. 1
1, 3, 9, 21 (list; graph; refs; listen; history; internal format)
OFFSET

1,2

COMMENTS

A similar pattern of construction to A000330 (dividing a square), A002717 (dividing a triangle), dividing a hexagon and any other polygon in a similar fashion (sequences pending).

CROSSREFS

Sequence in context: A196212 A146219 A197403 * A006077 A109612 A032668

Adjacent sequences:  A128124 A128125 A128126 * A128128 A128129 A128130

KEYWORD

easy,uned,nonn

AUTHOR

Noah Priluck (npriluck(AT)gmail.com), May 02 2007

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Last modified February 17 00:09 EST 2012. Contains 205978 sequences.