%I #18 Jan 23 2019 03:03:30
%S 2,6,42,7998,2611812210,1333641931958227433092278,
%T 178851409718295616588471418100320880488356072795626108481060122
%N a(n+1) = a(n) converted to base 6 from base 2 (written in base 10).
%H John Cerkan, <a href="/A023363/b023363.txt">Table of n, a(n) for n = 1..9</a>
%e 6 in binary is 110. Reinterpreting 110 in base 6 gives 1 * 6^2 + 1 * 6^1 + 0 * 6^0 = 36 + 6 = 42.
%t NestList[FromDigits[IntegerDigits[#, 2], 6] &, 2, 8] (* _Alonso del Arte_, Jan 22 2019 *)
%o (PARI) a(n) = if (n==1, 2, fromdigits(binary(a(n-1)), 6)); \\ _Michel Marcus_, Jan 22 2019
%Y Cf. A023362 (bases 2 & 5).
%K nonn,base
%O 1,1
%A _David W. Wilson_