A226953 - cp's OEIS frontend

A226953 Leap year numbers: numbers n such that tau(phi(n)) = phi(tau(n))^2, where tau(n) is the number of divisors of n and phi(n) the Euler totient function.

n	a(n)
1	1
2	2
3	9
4	14
5	15
6	18
7	20
8	22
9	46
10	94
11	118
12	166
13	214
14	231
15	248
16	286
17	308
18	310
19	334
20	344
21	350
22	351
23	358
24	366
25	372
26	392
27	399
28	405
29	406
30	430
31	454
32	483
33	490
34	494
35	516
36	518
37	522
38	526
39	532
40	536
41	568
42	595
43	598
44	632
45	638
46	644
47	654
48	663
49	666

[1, 2, 9, 14, 15, 18, 20, 22, 46, 94, 118, 166, 214, 231, 248, 286, 308, 310, 334, 344, 350, 351, 358, 366, 372, 392, 399, 405, 406, 430, 454, 483, 490, 494, 516, 518, 522, 526, 532, 536, 568, 595, 598, 632, 638, 644, 654, 663, 666]

cp's OEIS Frontend

A226953 Leap year numbers: numbers n such that tau(phi(n)) = phi(tau(n))^2, where tau(n) is the number of divisors of n and phi(n) the Euler totient function.

Table of values

List of values

n	a(n)
1	1
2	2
3	9
4	14
5	15
6	18
7	20
8	22
9	46
10	94
11	118
12	166
13	214
14	231
15	248
16	286
17	308
18	310
19	334
20	344
21	350
22	351
23	358
24	366
25	372
26	392
27	399
28	405
29	406
30	430
31	454
32	483
33	490
34	494
35	516
36	518
37	522
38	526
39	532
40	536
41	568
42	595
43	598
44	632
45	638
46	644
47	654
48	663
49	666

n	a(n)
1	1
2	2
3	9
4	14
5	15
6	18
7	20
8	22
9	46
10	94
11	118
12	166
13	214
14	231
15	248
16	286
17	308
18	310
19	334
20	344
21	350
22	351
23	358
24	366
25	372
26	392
27	399
28	405
29	406
30	430
31	454
32	483
33	490
34	494
35	516
36	518
37	522
38	526
39	532
40	536
41	568
42	595
43	598
44	632
45	638
46	644
47	654
48	663
49	666

n	a(n)
1	1
2	2
3	9
4	14
5	15
6	18
7	20
8	22
9	46
10	94
11	118
12	166
13	214
14	231
15	248
16	286
17	308
18	310
19	334
20	344
21	350
22	351
23	358
24	366
25	372
26	392
27	399
28	405
29	406
30	430
31	454
32	483
33	490
34	494
35	516
36	518
37	522
38	526
39	532
40	536
41	568
42	595
43	598
44	632
45	638
46	644
47	654
48	663
49	666