A275448 - cp's OEIS frontend

A275448 The number of weakly alternating bargraphs of semiperimeter n. A bargraph is said to be weakly alternating if its ascents and descents alternate. An ascent (descent) is a maximal sequence of consecutive U (D) steps.

n	a(n)
2	1
3	2
4	3
5	4
6	6
7	12
8	28
9	65
10	146
11	327
12	749
13	1756
14	4165
15	9913
16	23652
17	56687
18	136627
19	330969
20	804915
21	1963830
22	4805523
23	11793046
24	29019930
25	71589861
26	177006752
27	438561959
28	1088714711
29	2707615555
30	6745272783
31	16830750107
32	42058592797
33	105248042792

[1, 2, 3, 4, 6, 12, 28, 65, 146, 327, 749, 1756, 4165, 9913, 23652, 56687, 136627, 330969, 804915, 1963830, 4805523, 11793046, 29019930, 71589861, 177006752, 438561959, 1088714711, 2707615555, 6745272783, 16830750107, 42058592797, 105248042792]

cp's OEIS Frontend

A275448 The number of weakly alternating bargraphs of semiperimeter n. A bargraph is said to be weakly alternating if its ascents and descents alternate. An ascent (descent) is a maximal sequence of consecutive U (D) steps.

Table of values

List of values