a(n) is the number of subsets of {1, 2, ..., n} with product of all entries <= n^2 + n.

Terms

a(0) =0a(1) =2a(2) =4a(3) =8a(4) =14a(5) =26a(6) =40a(7) =58a(8) =84a(9) =114a(10) =148a(11) =194a(12) =242a(13) =306a(14) =370a(15) =454a(16) =532a(17) =624a(18) =736a(19) =848a(20) =986a(21) =1120a(22) =1274a(23) =1438a(24) =1618a(25) =1800a(26) =1994a(27) =2220a(28) =2446a(29) =2700