A372336 - cp's OEIS frontend

A372336 For a positive number k, let L(k) denote the list consisting of k followed by the prime factors of k, with repetition, in nondecreasing order; sequence gives composite k such that the digits of L(k) alternate being smaller than and then larger than the previous digit.

n	a(n)
1	6
2	51
3	91
4	106
5	219
6	323
7	406
8	435
9	437
10	518
11	529
12	609
13	614
14	626
15	629
16	634
17	658
18	703
19	705
20	818
21	826
22	838
23	878
24	906
25	938
26	978
27	2051
28	2093
29	2173
30	3053
31	3241
32	4151
33	4171
34	4281
35	5041
36	5063
37	5141
38	5183
39	5241
40	6251
41	6591
42	7021
43	7081
44	7251
45	8051
46	8121
47	8491
48	8571
49	8781
50	9121
51	9231
52	9291
53	9583

[6, 51, 91, 106, 219, 323, 406, 435, 437, 518, 529, 609, 614, 626, 629, 634, 658, 703, 705, 818, 826, 838, 878, 906, 938, 978, 2051, 2093, 2173, 3053, 3241, 4151, 4171, 4281, 5041, 5063, 5141, 5183, 5241, 6251, 6591, 7021, 7081, 7251, 8051, 8121, 8491, 8571, 8781, 9121, 9231, 9291, 9583]

cp's OEIS Frontend

A372336 For a positive number k, let L(k) denote the list consisting of k followed by the prime factors of k, with repetition, in nondecreasing order; sequence gives composite k such that the digits of L(k) alternate being smaller than and then larger than the previous digit.

Table of values

List of values