foaf and count in a sparql 1.1 query -

i'm beginner in sparql, great if me. . have rdf doc this:

  @prefix foaf: <http://xmlns.com/foaf/0.1/> .   @prefix lb:   <http://example.org/lastfm/> .    lb:bob     foaf:knows      lb:user2, lb:user3, lb:user4 ;        foaf:age        25 ;        lb:listenedto   lb:track1, lb:track2 ;        lb:topartist    lb:artist1, lb:artist2 .            lb:user2   foaf:knows      lb:user5, lb:user6 ;        foaf:age        40 ;        lb:listenedto   lb:track1, lb:track2, lb:track3 ;          lb:topartist    lb:artist2, lb:artist4 .            lb:user3   foaf:knows      lb:user5, lb:bob, lb:user6 ;        foaf:age        19 ;        lb:listenedto   lb:track2, lb:track3, lb:track4 ;        lb:topartist    lb:artist2, lb:artist3 .          lb:user4   lb:listenedto   lb:track2, lb:track3, lb:track4 ;        foaf:age        61 ;        lb:topartist    lb:artist3, lb:artist4, lb:artist5 .         lb:user5   foaf:knows      lb:user7 ;        foaf:age        23 ;        lb:topartist    lb:artist1, lb:artist3 . 

and want find users can reached lb:bob following foaf:knows @ 3 times , have listened @ least 2 tracks. wrote query this:

  prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>   prefix foaf: <http://xmlns.com/foaf/0.1/>   prefix lb:   <http://example.org/lastfm/>    select ?user     {    lb:bob foaf:knows | foaf:knows/foaf:knows| foaf:knows/foaf:knows/foaf:knows ?user.     ?user lb:listenedto ?tracks      minus{lb:bob lb:listenedto ?track}       filter (?tracks count(*)>=2)   } 

but error:

encountered " "count" "count "" @ line 12, column 23. expecting 1 of:  "not" ...  "in" ...  <integer_positive> ...  <decimal_positive> ...  <double_positive> ...  <integer_negative> ...  <decimal_negative> ...  <double_negative> ...  ")" ...  "=" ...  "!=" ...  ">" ...  "<" ...  "<=" ...  ">=" ...  "||" ...  "&&" ...  "+" ...  "-" ...  "*" ...  "/" ... 

i know query has lot of problems, please rewrite me?

how about:

prefix rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#> prefix foaf: <http://xmlns.com/foaf/0.1/> prefix lb:   <http://example.org/lastfm/>  select ?user {   lb:bob foaf:knows | foaf:knows/foaf:knows| foaf:knows/foaf:knows/foaf:knows ?user.   ?user lb:listenedto ?tracks } group ?user having (count(?tracks) > 2) 

you have minus in original query i'm not sure about. trying remove lb:bob binding ?user, perhaps? filter (?user != lb:bob) stop that.