Number of compositions of n avoiding the pattern 111.

Terms

a(0) =1a(1) =1a(2) =2a(3) =3a(4) =7a(5) =11a(6) =21a(7) =34a(8) =59a(9) =114a(10) =178a(11) =284a(12) =522a(13) =823a(14) =1352a(15) =2133a(16) =3739a(17) =5807a(18) =9063a(19) =14074a(20) =23639a(21) =36006a(22) =56914a(23) =87296a(24) =131142a(25) =214933a(26) =324644a(27) =487659a(28) =739291a(29) =1108457