A046203 Even numbers in the triangle of denominators in Leibniz's Harmonic Triangle.

2, 2, 6, 4, 12, 12, 4, 20, 30, 20, 6, 30, 60, 60, 30, 6, 42, 140, 42, 8, 56, 168, 280, 280, 168, 56, 8, 72, 252, 504, 630, 504, 252, 72, 10, 90, 360, 840, 1260, 1260, 840, 360, 90, 10, 110, 1320, 2310, 2772, 2310, 1320, 110, 12, 132, 660, 1980, 3960, 5544, 5544

Offset

1,1

References

L. Comtet, Advanced Combinatorics, Reidel, 1974, p. 83, Problem 25.

Links

Table of n, a(n) for n=1..58.

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; ...

Crossrefs

Cf. A003506.

Sequence in context: A278226 A190940 A336869 * A321451 A285943 A100495

Adjacent sequences: A046200 A046201 A046202 * A046204 A046205 A046206

Keyword

tabf,nonn,easy

Author

Mohammad K. Azarian

Extensions

More terms from James A. Sellers, Dec 13 1999

Status

approved