A226157 - cp's OEIS frontend

A226157 a(n) = BS2(n) * W(n) where BS2 = sum_{k=0..n} ((-1)^k*k!/(k+1)) S_{2}(n, k) and S_{2}(n, k) are the Stirling-Frobenius subset numbers A039755(n, k). W(n) = product{p primes <= n+1 such that p divides n+1 or p-1 divides n} = A225481(n).

n	a(n)
0	1
1	1
2	-2
3	-2
4	14
5	33
6	-62
7	-132
8	254
9	14585
10	-5110
11	-313266
12	2828954
13	38669001
14	-573370
15	-404801672
16	237036478
17	117650567067
18	-11499383114
19	-24255028327410
20	1281647882998
21	8203584532193105
22	-3584085584926
23	-418397193140056356
24	3965530936622474
25	405233976502715850633

[1, 1, -2, -2, 14, 33, -62, -132, 254, 14585, -5110, -313266, 2828954, 38669001, -573370, -404801672, 237036478, 117650567067, -11499383114, -24255028327410, 1281647882998, 8203584532193105, -3584085584926, -418397193140056356, 3965530936622474, 405233976502715850633]

cp's OEIS Frontend

A226157 a(n) = BS2(n) * W(n) where BS2 = sum_{k=0..n} ((-1)^k*k!/(k+1)) S_{2}(n, k) and S_{2}(n, k) are the Stirling-Frobenius subset numbers A039755(n, k). W(n) = product{p primes <= n+1 such that p divides n+1 or p-1 divides n} = A225481(n).

Table of values

List of values