|
Search: id:A160907
|
|
|
| A160907 |
|
Sum of prime divisors including repetitions between n^2 and (n+1)^2. |
|
+0
2
|
|
| 4, 11, 17, 23, 30, 34, 42, 50, 54, 58, 67
(list; graph; listen)
|
|
|
OFFSET
|
1,1
|
|
|
COMMENT
|
Example: between 1^2 and 2^2 we have 0,1,1,2 which sum to 4. Between 2^2 and 3^2 the number of divisors is 2,1,2,1,3,2 which sum to 11.
|
|
MATHEMATICA
|
s1= Array[Plus @@ Last/@ FactorInteger[ # ] &, 5000]; s2=Table[Sum[s1[[j]], {j, i^2, (i+1)^2}], {i, 1, 17}]
|
|
CROSSREFS
|
Sequence in context: A054870 A107988 A038241 this_sequence A003146 A063237 A026381
Adjacent sequences: A160904 A160905 A160906 this_sequence A160908 A160909 A160910
|
|
KEYWORD
|
easy,nonn
|
|
AUTHOR
|
Daniel Tisdale (daniel6874(AT)gmail.com), May 29 2009
|
|
|
Search completed in 0.002 seconds
|
