Number of strings of numbers x(i=1..n) in 0..2 with sum i^2*x(i) equal to n^2*2.

Terms

a(0) =1a(1) =1a(2) =2a(3) =1a(4) =5a(5) =7a(6) =10a(7) =20a(8) =37a(9) =77a(10) =118a(11) =227a(12) =385a(13) =697a(14) =1191a(15) =2072a(16) =3489a(17) =5846a(18) =9862a(19) =16373a(20) =26897a(21) =44125a(22) =71991a(23) =116290a(24) =187653a(25) =300903a(26) =478422a(27) =761553a(28) =1200692a(29) =1893309