|
Search: id:A112294
|
|
| |
|
| 1, 1, 4, 18, 121, 1055, 11376, 145852, 2165689, 36532197, 689873284, 14415662558, 330204013569, 8226714806323, 221470234531456, 6406397898751320, 198160750081637521, 6526636388676159977, 228040136335670652324
(list; graph; listen)
|
|
|
OFFSET
|
0,3
|
|
|
FORMULA
|
a(n)=sum{k=0..floor(n/2), (2n-2k-1)!!/(2k-1)!!}; a(n)=sum{k=0..floor(n/2), 2^(n-2k)(n-k-1/2)!/(k-1/2)!}; a(n)=sum{k=0..floor(n/2), (n-k)!C(2n-2k, n-k)2^(2k-n)/(k!C(2k, k))}; a(n)=sum{k=0..floor(n/2), (n-k+1)!*C(n-k)2^(2k-n)/((k+1)!*C(k))}.
|
|
CROSSREFS
|
Sequence in context: A053529 A005442 A084661 this_sequence A073511 A108704 A001423
Adjacent sequences: A112291 A112292 A112293 this_sequence A112295 A112296 A112297
|
|
KEYWORD
|
easy,nonn
|
|
AUTHOR
|
Paul Barry (pbarry(AT)wit.ie), Sep 01 2005
|
|
|
Search completed in 0.002 seconds
|
