Monotonic ordering of nonnegative differences 7^i-4^j, for 40>=i>=0, j>=0.

Terms

a(0) =0a(1) =3a(2) =6a(3) =33a(4) =45a(5) =48a(6) =87a(7) =279a(8) =327a(9) =339a(10) =342a(11) =423a(12) =1377a(13) =2145a(14) =2337a(15) =2385a(16) =2397a(17) =2400a(18) =12711a(19) =15783a(20) =16551a(21) =16743a(22) =16791a(23) =16803a(24) =16806a(25) =52113a(26) =101265a(27) =113553a(28) =116625a(29) =117393