Long legs of Pythagorean triangles.

Terms

a(0) =4a(1) =8a(2) =12a(3) =15a(4) =16a(5) =20a(6) =21a(7) =24a(8) =28a(9) =30a(10) =32a(11) =35a(12) =36a(13) =40a(14) =42a(15) =44a(16) =45a(17) =48a(18) =52a(19) =55a(20) =56a(21) =60a(22) =63a(23) =64a(24) =68a(25) =70a(26) =72a(27) =75a(28) =76a(29) =77