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A375191
Decimal expansion of the apothem (inradius) of a regular 11-gon with unit side length.
7
1, 7, 0, 2, 8, 4, 3, 6, 1, 9, 4, 4, 4, 6, 2, 5, 0, 0, 4, 5, 2, 4, 0, 6, 5, 1, 7, 3, 3, 2, 4, 4, 2, 4, 4, 1, 5, 9, 7, 8, 6, 4, 9, 9, 9, 3, 0, 6, 0, 9, 1, 4, 0, 7, 0, 4, 8, 8, 9, 6, 7, 0, 3, 0, 5, 3, 5, 9, 7, 6, 5, 3, 4, 5, 1, 3, 2, 9, 1, 0, 4, 8, 1, 1, 1, 4, 5, 7, 0, 2
OFFSET
1,2
LINKS
Eric Weisstein's World of Mathematics, Regular Polygon.
Wikipedia, Apothem.
FORMULA
Equals cot(Pi/11)/2.
Equals 1/(2*tan(Pi/11)).
Equals A375190*cos(Pi/11).
Equals A375190 - A375192.
EXAMPLE
1.702843619444625004524065173324424415978649993...
MATHEMATICA
First[RealDigits[Cot[Pi/11]/2, 10, 100]]
CROSSREFS
Cf. A375190 (circumradius), A375192 (sagitta), A256854 (area).
Cf. apothem of other polygons with unit side length: A020769 (triangle), A020761 (square), A375067 (pentagon), A010527 (hexagon), A374971 (heptagon), A174968 (octagon), A375152 (9-gon), A179452 (10-gon), A375193 (12-gon).
Sequence in context: A197014 A244979 A118288 * A094153 A243374 A309608
KEYWORD
nonn,cons,easy
AUTHOR
Paolo Xausa, Aug 04 2024
STATUS
approved