A024997 - cp's OEIS frontend

A024997 a(n) = number of (s(0), s(1), ..., s(n)) such that every s(i) is an integer, s(0) = 0 = s(n), |s(i) - s(i-1)| = 1 for i = 1,2; |s(i) - s(i-1)| <= 1 for i >= 3. Also a(n) = T(n,n), where T is the array defined in A024996.

n	a(n)
3	2
4	8
5	20
6	58
7	162
8	462
9	1318
10	3782
11	10886
12	31436
13	91016
14	264134
15	768094
16	2237640
17	6529284
18	19079574
19	55826166
20	163538472
21	479588844
22	1407813438
23	4136307798
24	12163015662
25	35793391662
26	105407889930
27	310620540202
28	915913267652
29	2702265079208

[2, 8, 20, 58, 162, 462, 1318, 3782, 10886, 31436, 91016, 264134, 768094, 2237640, 6529284, 19079574, 55826166, 163538472, 479588844, 1407813438, 4136307798, 12163015662, 35793391662, 105407889930, 310620540202, 915913267652, 2702265079208]

cp's OEIS Frontend

A024997 a(n) = number of (s(0), s(1), ..., s(n)) such that every s(i) is an integer, s(0) = 0 = s(n), |s(i) - s(i-1)| = 1 for i = 1,2; |s(i) - s(i-1)| <= 1 for i >= 3. Also a(n) = T(n,n), where T is the array defined in A024996.

Table of values

List of values