cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A251570 G.f. A(x) satisfies the condition that M(A(x)) is a power series in x consisting entirely of positive integer coefficients such that M(A(x) - x^k) has negative coefficients for k>0, where M(x) = 1 + x*M(x) + x*M(x)^2 is the g.f. of the Motzkin numbers A001006.

Table of values

n a(n)
1 1
2 0
3 -1
4 -1
5 1
6 0
7 -1
8 -1
9 0
10 1
11 -1
12 0
13 -1
14 -1
15 0
16 -1
17 -1
18 -1
19 0
20 -1
21 0
22 -1
23 0
24 0
25 0
26 -1
27 -1
28 -1
29 -1
30 0
31 0
32 -1
33 -1
34 0
35 -1
36 -1
37 0
38 0
39 -1
40 0
41 -1
42 0
43 -1
44 -1
45 -1
46 -1
47 -1
48 -1
49 0
50 -1
51 -1
52 -1
53 -1
54 0
55 -1
56 -1
57 -1
58 -2
59 0
60 0
61 0
62 0
63 0
64 0
65 0
66 0
67 0
68 -1
69 0
70 -1
71 -1
72 -1
73 -1
74 -1
75 0
76 0
77 -1
78 0
79 -1
80 0
81 -1
82 0
83 -1
84 -1
85 -1
86 0
87 -1
88 0
89 0
90 -1
91 -1
92 -1
93 -1
94 -1
95 -1
96 -1
97 -1
98 -1
99 -1
100 0
101 -1
102 0
103 0
104 -1
105 0
106 0
107 -1
108 0
109 -1
110 0
111 0
112 0
113 -1
114 0
115 -1
116 -1
117 0
118 -1
119 0
120 -1
121 -1
122 -1
123 -2
124 0
125 0
126 0
127 0
128 0
129 0
130 -1

List of values

[1, 0, -1, -1, 1, 0, -1, -1, 0, 1, -1, 0, -1, -1, 0, -1, -1, -1, 0, -1, 0, -1, 0, 0, 0, -1, -1, -1, -1, 0, 0, -1, -1, 0, -1, -1, 0, 0, -1, 0, -1, 0, -1, -1, -1, -1, -1, -1, 0, -1, -1, -1, -1, 0, -1, -1, -1, -2, 0, 0, 0, 0, 0, 0, 0, 0, 0, -1, 0, -1, -1, -1, -1, -1, 0, 0, -1, 0, -1, 0, -1, 0, -1, -1, -1, 0, -1, 0, 0, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, 0, -1, 0, 0, -1, 0, 0, -1, 0, -1, 0, 0, 0, -1, 0, -1, -1, 0, -1, 0, -1, -1, -1, -2, 0, 0, 0, 0, 0, 0, -1]