A386420 - cp's OEIS frontend

A386420 Odd numbers k that are closer to being perfect than previous terms and also satisfy the conditions that sigma(k) preserves the 3-adic valuation of k, and that sigma(k) == -k (mod 3).

n	a(n)
1	7
2	15
3	105
4	495
5	1365
6	2205
7	9405
8	26145
9	31815
10	497835
11	654675
12	1984455
13	7188885
14	9018009
15	9338595
16	9958905
17	13777785
18	13800465
19	14571585
20	47020995
21	78867495
22	132884115
23	210124665
24	363860775

[7, 15, 105, 495, 1365, 2205, 9405, 26145, 31815, 497835, 654675, 1984455, 7188885, 9018009, 9338595, 9958905, 13777785, 13800465, 14571585, 47020995, 78867495, 132884115, 210124665, 363860775]

cp's OEIS Frontend

A386420 Odd numbers k that are closer to being perfect than previous terms and also satisfy the conditions that sigma(k) preserves the 3-adic valuation of k, and that sigma(k) == -k (mod 3).

Table of values

List of values