A020991 - OEIS

A020991 as a simple table

n	a(n)
1	0
2	3
3	6
4	15
5	26
6	27
7	30
8	63
9	106
10	107
11	110
12	111
13	122
14	123
15	126
16	255
17	426
18	427
19	430
20	431
21	442
22	443
23	446
24	447
25	490
26	491
27	494
28	495
29	506
30	507
31	510
32	1023
33	1706
34	1707
35	1710
36	1711
37	1722
38	1723
39	1726
40	1727
41	1770
42	1771
43	1774
44	1775
45	1786
46	1787
47	1790
48	1791
49	1962
50	1963

[0,3,6,15,26,27,30,63,106,107,110,111,122,123,126, 255,426,427,430,431,442,443,446,447,490,491,494, 495,506,507,510,1023,1706,1707,1710,1711,1722, 1723,1726,1727,1770,1771,1774,1775,1786,1787,1790, 1791,1962,1963]