Number of subsets of {1, 2, ..., n} such that the sum of the reciprocals is strictly less than 1.

Terms

a(0) =1a(1) =1a(2) =2a(3) =4a(4) =7a(5) =13a(6) =24a(7) =44a(8) =81a(9) =149a(10) =274a(11) =501a(12) =918a(13) =1686a(14) =3110a(15) =5724a(16) =10543a(17) =19435a(18) =35857a(19) =66198a(20) =122294a(21) =226135a(22) =418351a(23) =774372a(24) =1434089a(25) =2657205a(26) =4925796a(27) =9135403a(28) =16949546a(29) =31460330