%I #18 Dec 21 2020 23:04:15
%S 1,2,4,7,8,11,13,14,16,19,21,22,25,26,28,32,35,37,38,41,42,44,49,50,
%T 52,56,64,67,69,70,73,74,76,81,82,84,88,97,98,100
%N a(1) = 1, a(2) = 2 and for n > 2, a(n) is the smallest number not of the form OR(a(i),a(j)) for 1 <= i < j < n.
%H Chai Wah Wu, <a href="/A333975/b333975.txt">Table of n, a(n) for n = 1..10000</a>
%t a[1] = 1; a[2] = 2;
%t a[n_] := a[n] =
%t For[k = a[n - 1] + 1, True, k++,
%t If[FreeQ[
%t Table[BitOr[a[i], a[j]], {i, 1, n - 2}, {j, i + 1, n - 1}], k],
%t Return[k]]];
%o (Python)
%o A333975_list, aset, m = [1,2], set(), 2
%o for i in range(3,10001):
%o for j in range(i-2):
%o aset.add(m|A333975_list[j])
%o m += 1
%o while m in aset:
%o m += 1
%o A333975_list.append(m) # _Chai Wah Wu_, Dec 21 2020
%K nonn
%O 1,2
%A _Michal D. Kuczynski_, Sep 03 2020