a(n) = a([ (n+1)/2 ]) + a([ (n+1)/3 ]) + . . . + a([ (n+1)/n ]).

Terms

a(0) =1a(1) =1a(2) =2a(3) =3a(4) =5a(5) =6a(6) =8a(7) =10a(8) =13a(9) =14a(10) =18a(11) =19a(12) =22a(13) =26a(14) =30a(15) =31a(16) =37a(17) =38a(18) =43a(19) =47a(20) =52a(21) =53a(22) =60a(23) =63a(24) =67a(25) =72a(26) =80a(27) =81a(28) =91a(29) =92