Smallest positive integer k such that 2^k has no '2' in the last n digits of its ternary expansion.

Terms

a(0) =2a(1) =2a(2) =6a(3) =8a(4) =8a(5) =8a(6) =20a(7) =24a(8) =24a(9) =24a(10) =72a(11) =186a(12) =186a(13) =332a(14) =332a(15) =1134a(16) =1134a(17) =1134a(18) =1134a(19) =1134a(20) =1134a(21) =25458a(22) =25458a(23) =25458a(24) =25458a(25) =25458a(26) =25458a(27) =159140a(28) =249968a(29) =249968