OFFSET
1,1
COMMENTS
MAPLE
Contribution from R. J. Mathar, Oct 29 2010: (Start)
A000695 := proc(n) local dgsa ; if n= 0 then 0; else for a from procname(n-1)+1 do dgsa := convert(convert(a, base, 4), set) ; if dgsa minus {0, 1} = {} then return a; end if; end do: end if; end proc:
MATHEMATICA
f[n_] := FromDigits[IntegerDigits[n, 2], 4]; s = Array[f, 150, 2]; div[a_, b_] := Divisible[a, b] && a > b; n = 1; While[Length[s] > n, s = Select[s, !div[#, s[[n]]] &]; n++]; s (* Amiram Eldar, Aug 31 2019 *)
CROSSREFS
KEYWORD
nonn
AUTHOR
Vladimir Shevelev, Nov 20 2008
EXTENSIONS
More terms from R. J. Mathar, Oct 29 2010
More terms from Amiram Eldar, Aug 31 2019
STATUS
approved