Square root of A030688.

Terms

a(0) =4a(1) =7a(2) =31a(3) =13a(4) =16a(5) =19a(6) =222a(7) =253a(8) =285a(9) =317a(10) =348a(11) =38a(12) =412a(13) =443a(14) =475a(15) =506a(16) =538a(17) =57a(18) =601a(19) =633a(20) =2101a(21) =696a(22) =728a(23) =759a(24) =791a(25) =2601a(26) =854a(27) =886a(28) =2901a(29) =949