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A046200
Odd numbers in the triangle of denominators in Leibniz's Harmonic Triangle.
0
1, 3, 3, 5, 5, 7, 105, 105, 7, 9, 9, 11, 495, 495, 11, 13, 6435, 6435, 13, 15, 1365, 15015, 45045, 45045, 15015, 1365, 15, 17, 17, 19, 2907, 2907, 19, 21, 101745, 101745, 21, 23, 5313, 168245, 1716099, 1716099, 168245, 5313, 23, 25, 18386775, 18386775, 25
OFFSET
1,2
REFERENCES
L. Comtet, Advanced Combinatorics, Reidel, 1974, p. 83, Problem 25.
EXAMPLE
1/1; --> 1
1/2, 1/2; -->
1/3, 1/6, 1/3; --> 3 3
1/4, 1/12, 1/12, 1/4; --> ...
1/5, 1/20, 1/30, 1/20, 1/5; ...
CROSSREFS
Cf. A003506.
Sequence in context: A247577 A282207 A376940 * A308415 A063281 A362059
KEYWORD
tabf,nonn,easy,less
EXTENSIONS
More terms from James A. Sellers, Dec 13 1999
STATUS
approved