A133952 - cp's OEIS frontend

A133952 a(n) = the number of "isolated divisors" of n!. A positive divisor, k, of n is isolated if neither (k-1) nor (k+1) divides n.

n	a(n)
1	1
2	0
3	1
4	4
5	10
6	19
7	43
8	77
9	137
10	243
11	497
12	749
13	1520
14	2518
15	3952
16	5294
17	10628
18	14564
19	29199
20	40855
21	60605
22	95786
23	191700
24	242580
25	339732
26	531896
27	677048
28	916946
29	1834106
30	2332346
31	4664982
32	5528982
33	7863685
34	12164443
35	16422235
36	19594843

[1, 0, 1, 4, 10, 19, 43, 77, 137, 243, 497, 749, 1520, 2518, 3952, 5294, 10628, 14564, 29199, 40855, 60605, 95786, 191700, 242580, 339732, 531896, 677048, 916946, 1834106, 2332346, 4664982, 5528982, 7863685, 12164443, 16422235, 19594843]

cp's OEIS Frontend

A133952 a(n) = the number of "isolated divisors" of n!. A positive divisor, k, of n is isolated if neither (k-1) nor (k+1) divides n.

Table of values

List of values