13 What is the Recamán Sequence?

A005132 – OEIS

The number sequence is named after the Colombian mathematician Bernardo Recamán Santos.

The numbers are calculated with the formula

The first numbers are
0,
1,
3,
6,
2,
7,
13,
20,
12,
21,
11,
22,
10,
23,
9,
24,
8,
25,
43,
62,
42,
63,
41,
18,
42,
17,
43,
16,
44,
15,
45,
14,
46,
79,
113,
78,
114,
77,
39,
78,
38,
79,
37,
80,
36,
81,
35,
82,
34,
83,
33,
84,
32,
85,
31,
86,
30,
87,
29,
88,
28,
89,
27,
90,
26,
91,
157,
224,
156,
225,
155