%I #9 Aug 07 2024 02:32:46

%S 1,1,4,1,2,1,7,3,7,1,9,5,0,7,4,9,6,9,0,3,8,8,0,5,6,8,1,0,3,0,5,0,7,3,

%T 9,1,3,6,9,3,9,0,8,4,0,4,9,0,1,7,6,3,1,8,9,8,9,8,4,4,4,5,9,8,0,1,9,1,

%U 2,4,2,7,8,5,6,9,4,0,9,3,9,4,5,7,3,4,6,9,3,5

%N Decimal expansion of the sagitta of a regular heptagon with unit side length.

%H Paolo Xausa, <a href="/A374972/b374972.txt">Table of n, a(n) for n = 0..10000</a>

%H Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/RegularPolygon.html">Regular Polygon</a>.

%H Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/Sagitta.html">Sagitta</a>.

%F Equals tan(Pi/14)/2 = A343059/2.

%F Equals A374957 - A374971.

%e 0.114121737195074969038805681030507391369390840490...

%t First[RealDigits[Tan[Pi/14]/2, 10, 100]]

%Y Cf. A374957 (circumradius), A374971 (apothem), A178817 (area).

%Y Cf. sagitta of other polygons with unit side length: A020769 (triangle), A174968 (square), A375068 (pentagon), A375069 (hexagon), A374972 (heptagon), A375070 (octagon), A375153 (9-gon), A375189 (10-gon), A375192 (11-gon), A375194 (12-gon).

%Y Cf. A343059.

%K nonn,cons,easy

%O 0,3

%A _Paolo Xausa_, Jul 26 2024