|
Search: id:A085738
|
|
|
| A085738 |
|
Denominators in triangle formed from Bernoulli numbers. |
|
+0 2
|
|
| 1, 2, 2, 6, 3, 6, 1, 6, 6, 1, 30, 30, 15, 30, 30, 1, 30, 15, 15, 30, 1, 42, 42, 105, 105, 105, 42, 42, 1, 42, 21, 105, 105, 21, 42, 1, 30, 30, 105, 105, 105, 105, 105, 30, 30, 1, 30, 15, 105, 105, 105, 105, 15, 30, 1, 66, 66, 165, 165, 1155, 231, 1155, 165
(list; graph; listen)
|
|
|
OFFSET
|
0,2
|
|
|
COMMENT
|
Triangle is determined by rules 0) the top number is 1; 1) each number is the sum of the two below it; 2) it is left-right symmetric; 3) the numbers in each of the border rows, after the first 3, are alternately 0.
|
|
FORMULA
|
T(n, 0) = (-1)^n*Bernoulli(n), T(n, k) = T(n-1, k-1) + T(n, k-1) for k=1..n.
|
|
EXAMPLE
|
Triangle begins
1
1/2, 1/2
1/6, 1/3, 1/6
0, 1/6, 1/6, 0
-1/30, 1/30, 2/15, 1/30, -1/30
0, -1/30, 1/15, 1/15, -1/30, 0
1/42, -1/42, -1/105, 8/105, -1/105, -1/42, 1/42
0, 1/42, -1/21, 4/105, 4/105, -1/21, 1/42, 0
-1/30, 1/30, -1/105, -4/105, 8/105, -4/105, -1/105, 1/30, -1/30
|
|
CROSSREFS
|
Cf. A085737. See A051714/A051715 for another triangle that generates the Bernoulli numbers.
Sequence in context: A100346 A130478 A128623 this_sequence A100641 A028421 A081745
Adjacent sequences: A085735 A085736 A085737 this_sequence A085739 A085740 A085741
|
|
KEYWORD
|
nonn,frac
|
|
AUTHOR
|
njas following a suggestion of J. H. Conway, Jul 23 2003
|
|
|
Search completed in 0.002 seconds
|