A138368 - OEIS

A138368 as a simple table

n	a(n)
1	13
2	37
3	61
4	181
5	373
6	541
7	853
8	1237
9	1381
10	1693
11	1861
12	2221
13	3037
14	3733
15	7237
16	7933
17	8293
18	9421
19	12781
20	14173
21	14653
22	16141
23	19333
24	25933
25	27901
26	28573
27	30637
28	34981
29	36493
30	38821
31	41221
32	44533
33	46237
34	49741
35	52453
36	60037
37	70237
38	73453
39	87037

[13,37,61,181,373,541,853,1237,1381,1693,1861, 2221,3037,3733,7237,7933,8293,9421,12781,14173, 14653,16141,19333,25933,27901,28573,30637,34981, 36493,38821,41221,44533,46237,49741,52453,60037, 70237,73453,87037]