Sums of 3 distinct powers of 3.

Terms

a(0) =13a(1) =31a(2) =37a(3) =39a(4) =85a(5) =91a(6) =93a(7) =109a(8) =111a(9) =117a(10) =247a(11) =253a(12) =255a(13) =271a(14) =273a(15) =279a(16) =325a(17) =327a(18) =333a(19) =351a(20) =733a(21) =739a(22) =741a(23) =757a(24) =759a(25) =765a(26) =811a(27) =813a(28) =819a(29) =837