A100069 - cp's OEIS frontend

A100069 a(n) = Sum_{k=0..floor(n/2)} binomial(n,k)4^(n-2k).

n	a(n)
0	1
1	4
2	18
3	76
4	326
5	1384
6	5892
7	25036
8	106438
9	452344
10	1922588
11	8170936
12	34726940
13	147589264
14	627256088
15	2665837516
16	11329815878
17	48151714264
18	204644809932
19	869740430056
20	3696396920116
21	15709686864304
22	66766169526008
23	283756220309176
24	1205963937666076
25	5125346734404784

[1, 4, 18, 76, 326, 1384, 5892, 25036, 106438, 452344, 1922588, 8170936, 34726940, 147589264, 627256088, 2665837516, 11329815878, 48151714264, 204644809932, 869740430056, 3696396920116, 15709686864304, 66766169526008, 283756220309176, 1205963937666076, 5125346734404784]

cp's OEIS Frontend

A100069 a(n) = Sum_{k=0..floor(n/2)} binomial(n,k)4^(n-2k).

Table of values

List of values

cp's OEIS Frontend

A100069 a(n) = Sum_{k=0..floor(n/2)} binomial(n,k)*4^(n-2*k).

Table of values

List of values

A100069 a(n) = Sum_{k=0..floor(n/2)} binomial(n,k)4^(n-2k).