A121174 Sequence S with property (making all terms distinct) that (i) a(1)=3, (ii) for n is S, a(n)=a(1)+a(2)+...+a(n-1), (iii) for n not in S, a(n)=the smallest number different from a(1), ..., a(n-1) not breaking condition (ii).
3, 4, 7, 14, 6, 34, 68, 9, 145, 11, 301, 13, 615, 1230, 16, 2476, 18, 4970, 20, 9960, 22, 19942, 24, 39908, 26, 79842, 28, 159712, 30, 319454, 32, 638940, 35, 1277915, 2555830, 37, 5111697, 39, 10223433, 41, 20446907, 43, 40893857, 45
Offset: 1