Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).
%I #6 Feb 03 2014 12:46:14
%S 1,2,3,4,5,6,49,51,52,53,54,55,98,99,101,102,103,104,147,148,149,151,
%T 152,153,196,197,198,199,201,202,245,246,247,248,249,251,294,295,296,
%U 297,298,299,2402,2403,2404,2405,2406,2407,2499
%N a(n)=A033005(n)/8.
%C Numbers which, written in base 49, have only digits 0 through 6 and no two adjacent digits equal. - _M. F. Hasler_, Feb 03 2014
%o (PARI) is_A043311(n)=(n=[n])&&!until(!n[1],((n=divrem(n[1],49))[2]<7 && n[1]%7!=n[2])||return) \\ _M. F. Hasler_, Feb 03 2014
%Y Cf. A043307 - A043320, A043291, A033001 - A033014, A033016 - A033029. ~
%K nonn,base
%O 1,2
%A _Clark Kimberling_