A245060 - cp's OEIS frontend

A245060 a(n) = Sum_{k=1..n} C(n-1,k-1) * S2(n,k) * 3^(n-k) for n>0, a(0)=1, where S2(n,k) = A048993(n,k) are Stirling numbers of the 2nd kind.

n	a(n)
0	1
1	1
2	4
3	28
4	271
5	3172
6	43174
7	666577
8	11445214
9	215478712
10	4401799930
11	96757165012
12	2273105615356
13	56755763435503
14	1499039156935948
15	41714498328290992
16	1218787798107634291
17	37275555462806318512
18	1190200470204107432854
19	39581409916012393962280
20	1368112674516484881342244

[1, 1, 4, 28, 271, 3172, 43174, 666577, 11445214, 215478712, 4401799930, 96757165012, 2273105615356, 56755763435503, 1499039156935948, 41714498328290992, 1218787798107634291, 37275555462806318512, 1190200470204107432854, 39581409916012393962280, 1368112674516484881342244]

cp's OEIS Frontend

A245060 a(n) = Sum_{k=1..n} C(n-1,k-1) * S2(n,k) * 3^(n-k) for n>0, a(0)=1, where S2(n,k) = A048993(n,k) are Stirling numbers of the 2nd kind.

Table of values

List of values