|
Search: id:A120995
|
|
|
| A120995 |
|
Denominators of rationals related to John Wallis' product formula for pi/2 (from his 'Arithmetica infinitorum' from 1659). |
|
+0
3
|
|
| 1, 15, 175, 3675, 14553, 231231, 920205, 234652275, 2807136475, 14933966047, 59612442981, 11425718238025, 15211755050625, 243077636829375, 971230202264925, 993568496917018275, 3970836034391543625
(list; graph; listen)
|
|
|
OFFSET
|
1,2
|
|
|
COMMENT
|
The corresponding numerators are A120994.
The rationals W(n):= (((4^n)/binomial(2*n,n))^2)/(2*n+1) converge to pi/2 = 1.570796327...
|
|
FORMULA
|
a(n)=denominators((3/4)*W(n)), n>=1.
|
|
CROSSREFS
|
Sequence in context: A000482 A145147 A069379 this_sequence A024197 A071535 A081043
Adjacent sequences: A120992 A120993 A120994 this_sequence A120996 A120997 A120998
|
|
KEYWORD
|
nonn,easy,frac
|
|
AUTHOR
|
Wolfdieter Lang (wolfdieter.lang(AT)physik.uni-karlsruhe.de), Aug 01 2006
|
|
|
Search completed in 0.004 seconds
|
