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A140249
Decimal expansion of 3*sqrt(15)/2.
12
5, 8, 0, 9, 4, 7, 5, 0, 1, 9, 3, 1, 1, 1, 2, 5, 3, 2, 7, 7, 6, 8, 8, 9, 8, 0, 9, 9, 6, 7, 3, 5, 9, 9, 4, 1, 6, 2, 4, 9, 3, 8, 2, 5, 5, 7, 9, 3, 7, 3, 8, 6, 2, 3, 9, 8, 8, 1, 3, 6, 0, 6, 4, 9, 1, 7, 0, 2, 2, 4, 6, 3, 7, 9, 0, 5, 4, 6, 8, 5, 5, 0, 2, 7, 8, 9, 3, 1, 0, 6, 5, 2, 8, 8, 0, 1, 0, 2, 7, 6, 8, 7, 4, 4, 5
OFFSET
1,1
COMMENTS
Exradius opposite the side of length 4 of the obtuse scalene triangle with sides of lengths 2, 3 and 4, the scalene triangle with least integer side lengths. See formulas in the Weisstein link.
LINKS
Eric Weisstein's World of Mathematics, Exradius.
FORMULA
3*sqrt(15)/2 = 3*A010472/2 = 2*A140239 = 3*A088543 = 5*A140248.
EXAMPLE
5.80947501931112532776889809967359941624938255793738623988136064917022463790...
MATHEMATICA
First[RealDigits[3 Sqrt[15]/2, 10, 100]] (* Paolo Xausa, Oct 30 2023 *)
PROG
(PARI) 3*sqrt(15)/2
KEYWORD
cons,nonn
AUTHOR
Rick L. Shepherd, May 14 2008
STATUS
approved