Smallest number that has exactly n substrings which are square.

Terms

a(0) =2a(1) =0a(2) =10a(3) =49a(4) =100a(5) =1000a(6) =1441a(7) =4900a(8) =11449a(9) =104900a(10) =144100a(11) =490000a(12) =1440000a(13) =1144900a(14) =11144900a(15) =16810000a(16) =114490049a(17) =156250000a(18) =114490000a(19) =1114490000a(20) =1681000000