a(n) and floor(a(n)/5) are both squares; i.e., squares which remain squares when written in base 5 and last digit is removed.

A055812

a(n) and floor(a(n)/5) are both squares; i.e., squares which remain squares when written in base 5 and last digit is removed.

Terms

    a(0) =0a(1) =1a(2) =4a(3) =9a(4) =49a(5) =81a(6) =324a(7) =2209a(8) =15129a(9) =25921a(10) =103684a(11) =710649a(12) =4870849a(13) =8346321a(14) =33385284a(15) =228826129a(16) =1568397609a(17) =2687489281a(18) =10749957124a(19) =73681302249a(20) =505019158609a(21) =865363202001

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