

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
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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 A273317 A122866
Adjacent sequences: A046199 A046200 A046201 * A046203 A046204 A046205


KEYWORD

tabf,nonn,easy


AUTHOR

Mohammad K. Azarian


EXTENSIONS

More terms from James A. Sellers, Dec 13 1999


STATUS

approved



