Numbers of the form 3^j + 7^k, for j and k >= 0.

Terms

a(0) =2a(1) =4a(2) =8a(3) =10a(4) =16a(5) =28a(6) =34a(7) =50a(8) =52a(9) =58a(10) =76a(11) =82a(12) =88a(13) =130a(14) =244a(15) =250a(16) =292a(17) =344a(18) =346a(19) =352a(20) =370a(21) =424a(22) =586a(23) =730a(24) =736a(25) =778a(26) =1072a(27) =2188a(28) =2194a(29) =2236