Numbers of the form (7^i)*(13^j).

Terms

a(0) =1a(1) =7a(2) =13a(3) =49a(4) =91a(5) =169a(6) =343a(7) =637a(8) =1183a(9) =2197a(10) =2401a(11) =4459a(12) =8281a(13) =15379a(14) =16807a(15) =28561a(16) =31213a(17) =57967a(18) =107653a(19) =117649a(20) =199927a(21) =218491a(22) =371293a(23) =405769a(24) =753571a(25) =823543a(26) =1399489a(27) =1529437a(28) =2599051a(29) =2840383