Number of 4-sided prudent polygons of area n.

Terms

a(0) =8a(1) =16a(2) =40a(3) =96a(4) =232a(5) =560a(6) =1336a(7) =3176a(8) =7480a(9) =17528a(10) =40776a(11) =94336a(12) =216976a(13) =496432a(14) =1130120a(15) =2560648a(16) =5776304a(17) =12976112a(18) =29036008a(19) =64732992a(20) =143814192a(21) =318455632a(22) =702983256a(23) =1547254832a(24) =3395989288a(25) =7433962168a(26) =16232357608a(27) =35359307144a(28) =76848753032a(29) =166658534216