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A059367
From solution to x = tan x (next term is not an integer).
0
1, 2, 13, 146, 2343, 48984
OFFSET
0,2
COMMENTS
Suppose 1/y = 1/x + arctan(x). Then arctan(x) = Sum_{n>=0} a(n) * y^(2n+1)/(2n+1)!!. Note that a(6) = 6316012/5. a(7) = 38759594. - Michael Somos, Jan 01 2021
REFERENCES
L. Comtet, Advanced Combinatorics, Reidel, 1974, p. 171, #33.
CROSSREFS
Cf. A079330.
Sequence in context: A377599 A107699 A079330 * A309799 A324464 A373179
KEYWORD
nonn
AUTHOR
N. J. A. Sloane, Jan 28 2001
STATUS
approved