A356889 - cp's OEIS frontend

A356889 a(n) = (n^2 + 3n + 10/3)4^(n-3) - 1/3.

n	a(n)
2	3
3	21
4	125
5	693
6	3669
7	18773
8	93525
9	456021
10	2184533
11	10310997
12	48059733
13	221599061
14	1012225365
15	4585772373
16	20624790869
17	92162839893
18	409453548885
19	1809612887381
20	7960006055253
21	34863681197397
22	152099108509013
23	661172992169301
24	2864594294232405
25	12373170851239253

[3, 21, 125, 693, 3669, 18773, 93525, 456021, 2184533, 10310997, 48059733, 221599061, 1012225365, 4585772373, 20624790869, 92162839893, 409453548885, 1809612887381, 7960006055253, 34863681197397, 152099108509013, 661172992169301, 2864594294232405, 12373170851239253]

cp's OEIS Frontend

A356889 a(n) = (n^2 + 3n + 10/3)4^(n-3) - 1/3.

Table of values

List of values

cp's OEIS Frontend

A356889 a(n) = (n^2 + 3*n + 10/3)*4^(n-3) - 1/3.

Table of values

List of values

A356889 a(n) = (n^2 + 3n + 10/3)4^(n-3) - 1/3.