|
Search: id:A110957
|
|
|
| A110957 |
|
(Sum{k=1..n} 1/c(k))*(product{j=1..n} c(j)), where c(j) is j-th composite. |
|
+0
1
|
|
| 1, 10, 104, 1128, 13008, 173376, 2634624, 42422400, 722304000, 13698201600, 286505164800, 6267431116800, 143150760345600, 3551498315366400, 91568579493888000, 2450311107084288000, 67966128937598976000
(list; graph; listen)
|
|
|
OFFSET
|
1,2
|
|
|
EXAMPLE
|
Since the first 3 composites are 4, 6, and 8, the third term of the sequence is
(1/4 +1/6 +1/8) *4 *6 *8 = 48 +32 +24 = 104.
|
|
MAPLE
|
c:=proc(n) if isprime(n)=false then n else fi end: C:=[seq(c(n), n=2..35)]: a:=n->sum(1/C[k], k=1..n)*product(C[j], j=1..n): seq(a(n), n=1..20); (Deutsch)
|
|
CROSSREFS
|
Cf. A002808, A024451.
Sequence in context: A015588 A027270 A036334 this_sequence A077671 A117832 A117833
Adjacent sequences: A110954 A110955 A110956 this_sequence A110958 A110959 A110960
|
|
KEYWORD
|
nonn
|
|
AUTHOR
|
Leroy Quet (qq-quet(AT)mindspring.com), Sep 26 2005
|
|
EXTENSIONS
|
More terms from Emeric Deutsch (deutsch(AT)duke.poly.edu), Oct 06 2005
|
|
|
Search completed in 0.002 seconds
|
