Squares in whose primorial base expansion only even digits appear.

Terms

a(0) =0a(1) =4a(2) =16a(3) =64a(4) =144a(5) =196a(6) =484a(7) =900a(8) =1024a(9) =1444a(10) =1764a(11) =2116a(12) =2304a(13) =4624a(14) =5184a(15) =5476a(16) =6084a(17) =6724a(18) =13924a(19) =14400a(20) =14884a(21) =18496a(22) =19044a(23) =20164a(24) =23104a(25) =23716a(26) =24964a(27) =28224a(28) =29584a(29) =61504