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 A046202 Distinct numbers in the triangle of denominators in Leibniz's Harmonic Triangle. 2
 1, 2, 3, 6, 4, 12, 5, 20, 30, 60, 7, 42, 105, 140, 8, 56, 168, 280, 9, 72, 252, 504, 630, 10, 90, 360, 840, 1260, 11, 110, 495, 1320, 2310, 2772, 132, 660, 1980, 3960, 5544, 13, 156, 858, 2860, 6435, 10296, 12012, 14, 182, 1092, 4004, 10010, 18018, 24024, 15 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Numbers in the order in which they appear in Leibniz's Harmonic Triangle (A003506). This sequence is a permutation of the natural numbers. - Robert G. Wilson v, Jun 12 2014 REFERENCES L. Comtet, Advanced Combinatorics, Reidel, 1974, p. 83, Problem 25. LINKS Ivan Neretin, Table of n, a(n) for n = 1..10000 EXAMPLE 1/1; 1/2, 1/2; 1/3, 1/6, 1/3; 1/4, 1/12, 1/12, 1/4; 1/5, 1/20, 1/30, 1/20, 1/5; ... MATHEMATICA t[n_, k_] := Denominator[n!*k!/(n + k + 1)!]; DeleteDuplicates@ Flatten@ Table[t[n - k, k], {n, 0, 14}, {k, 0, n/2}] (* Robert G. Wilson v, Jun 12 2014 *) CROSSREFS Cf. A003506, A046201, A014631. Sequence in context: A049449 A104663 A246429 * A225642 A122866 A097275 Adjacent sequences:  A046199 A046200 A046201 * A046203 A046204 A046205 KEYWORD tabf,nonn,easy AUTHOR EXTENSIONS More terms from James A. Sellers, Dec 13 1999 STATUS approved

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