A243996 - cp's OEIS frontend

A243996 Numbers n such that phi(sigma(n)) = sigma(phi(n)), where sigma*(n) is the sum of anti-divisors of n and phi(n) is the Euler totient function.

n	a(n)
1	7
2	9
3	20
4	25
5	80
6	143
7	825
8	3117
9	3216
10	22774
11	52026
12	55804
13	138276
14	187733
15	228384
16	265545
17	320766
18	549540
19	830814
20	839784
21	901376
22	1293552
23	1315776
24	2635866
25	6771114
26	11126800
27	12087848
28	24351460
29	49382242
30	52344292
31	60063744
32	65980038
33	78279016
34	97638080

[7, 9, 20, 25, 80, 143, 825, 3117, 3216, 22774, 52026, 55804, 138276, 187733, 228384, 265545, 320766, 549540, 830814, 839784, 901376, 1293552, 1315776, 2635866, 6771114, 11126800, 12087848, 24351460, 49382242, 52344292, 60063744, 65980038, 78279016, 97638080]

cp's OEIS Frontend

A243996 Numbers n such that phi(sigma(n)) = sigma(phi(n)), where sigma*(n) is the sum of anti-divisors of n and phi(n) is the Euler totient function.

Table of values

List of values

cp's OEIS Frontend

A243996 Numbers n such that phi(sigma*(n)) = sigma*(phi(n)), where sigma*(n) is the sum of anti-divisors of n and phi(n) is the Euler totient function.

Table of values

List of values

A243996 Numbers n such that phi(sigma(n)) = sigma(phi(n)), where sigma*(n) is the sum of anti-divisors of n and phi(n) is the Euler totient function.