Number of subsets of {1..n} whose cardinality is equal to the root-mean-square of the elements.

Terms

a(0) =1a(1) =1a(2) =1a(3) =1a(4) =1a(5) =1a(6) =1a(7) =1a(8) =3a(9) =4a(10) =5a(11) =10a(12) =16a(13) =32a(14) =56a(15) =90a(16) =134a(17) =186a(18) =304a(19) =476a(20) =746a(21) =1308a(22) =2522a(23) =4845a(24) =9129a(25) =17260a(26) =32684a(27) =59908a(28) =106181a(29) =191779