Squares in A386687.

Terms

a(0) =0a(1) =1a(2) =9a(3) =81a(4) =225a(5) =1369a(6) =2209a(7) =13689a(8) =106929a(9) =915849a(10) =8105409a(11) =72539289a(12) =651627729a(13) =1097530641a(14) =1108290681a(15) =2176502409a(16) =4469591025a(17) =21803770921a(18) =26143332721a(19) =47825753481a(20) =253493117361a(21) =396488086929a(22) =845198906409