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A085550
Decimal expansion of (sqrt(13)-3)/2.
6
3, 0, 2, 7, 7, 5, 6, 3, 7, 7, 3, 1, 9, 9, 4, 6, 4, 6, 5, 5, 9, 6, 1, 0, 6, 3, 3, 7, 3, 5, 2, 4, 7, 9, 7, 3, 1, 2, 5, 6, 4, 8, 2, 8, 6, 9, 2, 2, 6, 2, 3, 1, 0, 6, 3, 5, 5, 2, 2, 6, 5, 2, 8, 1, 1, 3, 5, 8, 3, 4, 7, 4, 1, 4, 6, 5, 0, 5, 2, 2, 2, 6, 0, 2, 3, 0, 9, 5, 4, 1, 0, 0, 9, 2, 4, 5, 3, 5, 8, 8, 3, 6, 7, 5, 7
OFFSET
0,1
LINKS
Cino Hilliard, + N = Reciprocal Recursion [broken link]
FORMULA
Equals Sum_{k>=1} (-1)^(k-1)/(A006190(k)*A006190(k+1)). - Vladimir Shevelev, Feb 23 2013
Tan(arctan(c) + arctan(c^3)) = 1/3. - Gary W. Adamson, Apr 02 2024
EXAMPLE
0.30277563773199464655961...
MATHEMATICA
First[RealDigits[(Sqrt[13] - 3)/2, 10, 100]] (* Paolo Xausa, Jun 12 2024 *)
PROG
(PARI) (sqrt(13)-3)/2 \\ Michel Marcus, Jan 16 2020
CROSSREFS
Cf. A010470 (sqrt(13)).
Sequence in context: A374062 A011075 A248820 * A223139 A302278 A302728
KEYWORD
easy,cons,nonn
AUTHOR
Cino Hilliard, Jul 04 2003
STATUS
approved