|
| |
|
|
A074251
|
|
Sum of squarefree numbers from the smallest prime factor of n to the largest prime factor of n.
|
|
0
| |
|
|
0, 2, 3, 2, 5, 5, 7, 2, 3, 10, 11, 5, 13, 23, 8, 2, 17, 5, 19, 10, 21, 44, 23, 5, 5, 57, 3, 23, 29, 10, 31, 2, 42, 103, 18, 5, 37, 122, 55, 10, 41, 23, 43, 44, 8, 188, 47, 5, 7, 10, 101, 57, 53, 5, 39, 23, 120, 243, 59, 10, 61, 304, 21, 2, 52, 44, 67, 103, 186, 23, 71, 5, 73
(list; graph; refs; listen; history; internal format)
|
|
|
|
OFFSET
| 1,2
|
|
|
EXAMPLE
| a(22)=44 because 22=2*11 and the sum of squarefree numbers between 2 and 11 is: 2+3+5+6+7+10+11 = 44.
|
|
|
MAPLE
| with(numtheory): a:=proc(n) local nf, nnf, s, j: nf:=factorset(n): nnf:=nops(nf): s:=0: for j from nf[1] to nf[nnf] do if abs(mobius(j))>0 then s:=s+j else s:=s: fi: od: s: end: 0, seq(a(n), n=2..84); (Emeric Deutsch)
|
|
|
CROSSREFS
| Cf. A005117.
Sequence in context: A008472 A123528 A074036 * A074196 A153023 A068319
Adjacent sequences: A074248 A074249 A074250 * A074252 A074253 A074254
|
|
|
KEYWORD
| nonn
|
|
|
AUTHOR
| Jason Earls (zevi_35711(AT)yahoo.com), Sep 20 2002
|
| |
|
|
