Number of compositions of n in which the minimal multiplicity of parts equals 1.

Terms

a(0) =1a(1) =1a(2) =3a(3) =6a(4) =15a(5) =23a(6) =53a(7) =94a(8) =203a(9) =404a(10) =855a(11) =1648a(12) =3416a(13) =6662a(14) =13400a(15) =26406a(16) =53038a(17) =105306a(18) =212051a(19) =422162a(20) =849267a(21) =1696864a(22) =3406077a(23) =6807024a(24) =13642099a(25) =27268122a(26) =54576003a(27) =109096436a(28) =218250874a(29) =436243705