|
Search: id:A136364
|
|
|
| A136364 |
|
a(n) = Sum_{ composite k, 1 <= k <= 10^n} (Number of divisors d of k with 1 < d < k). |
|
+0
2
|
| |
|
|
OFFSET
|
1,1
|
|
|
EXAMPLE
|
a(1)=8 because there are 8 distinct divisors of composite numbers k through 10^1; these are for 4(1); 6(2); 8(2); 9(1); 10(2); and 1+2+2+1+2=8.
|
|
CROSSREFS
|
Cf. A136363.
Sequence in context: A129424 A045479 A079929 this_sequence A089670 A060355 A060859
Adjacent sequences: A136361 A136362 A136363 this_sequence A136365 A136366 A136367
|
|
KEYWORD
|
easy,more,nonn
|
|
AUTHOR
|
Enoch Haga (Enokh(AT)comcast.net), Dec 26 2007, Dec 29 2007
|
|
EXTENSIONS
|
Edited by njas, Jan 12 2008
|
|
|
Search completed in 0.002 seconds
|
