|
Search: id:A002503
|
|
|
| A002503 |
|
Numbers n such that binomial(2n,n) is divisible by (n+1)^2.
(Formerly M3840)
|
|
+0
5
|
|
| 5, 14, 27, 41, 44, 65, 76, 90, 109, 125, 139, 152, 155, 169, 186, 189, 203, 208, 209, 219, 227, 230, 237, 265, 275, 298, 307, 311, 314, 321, 324, 329, 344, 377, 413, 419, 428, 434, 439, 441, 449, 458, 459, 467, 475
(list; graph; listen)
|
|
|
OFFSET
|
1,1
|
|
|
REFERENCES
|
H. Balakran, On the values of n which make (2n)!/(n+1)!(n+1)! an integer, J. Indian Math. Soc., Vol. 18, 1929, 97-100.
P. Erdos, R. L. Graham, I. Z. Ruzsa and E. G. Straus, On the prime factors of C(2n,n), Math. Comp. 29 (1975), 83-92.
|
|
LINKS
|
T. D. Noe, Table of n, a(n) for n=1..1000
|
|
CROSSREFS
|
Positions of zeros in A065350.
Cf. A000108, A065344-A065349.
A067348(n+2)/2 - 1.
Sequence in context: A030745 A071421 A065351 this_sequence A014106 A110325 A140342
Adjacent sequences: A002500 A002501 A002502 this_sequence A002504 A002505 A002506
|
|
KEYWORD
|
nonn,easy,nice
|
|
AUTHOR
|
njas, Mira Bernstein (mira(AT)math.berkeley.edu)
|
|
EXTENSIONS
|
Balakran reference corrected by T. D. Noe, Jan 16 2007
|
|
|
Search completed in 0.002 seconds
|
