Number of subsets of {1,2,3,...,n} whose sum is a square integer (including the empty subset).

Terms

a(0) =1a(1) =2a(2) =2a(3) =3a(4) =5a(5) =7a(6) =12a(7) =20a(8) =34a(9) =60a(10) =106a(11) =190a(12) =346a(13) =639a(14) =1183a(15) =2204a(16) =4129a(17) =7758a(18) =14642a(19) =27728a(20) =52648a(21) =100236a(22) =191294a(23) =365827a(24) =700975a(25) =1345561a(26) =2587057a(27) =4981567a(28) =9605777a(29) =18546389