Sequences
392,541 sequences
- Number of connected labeled 2-regular oriented graphs with n nodes.A007110
Number of connected labeled 2-regular oriented graphs with n nodes.
- Number of unlabeled graphs with n nodes and degree >= 3.A007111
Number of unlabeled graphs with n nodes and degree >= 3.
- Number of connected unlabeled graphs with n nodes and degree >= 3.A007112
Number of connected unlabeled graphs with n nodes and degree >= 3.
- Expansion of e.g.f. (1 + x)^x.A007113
Expansion of e.g.f. (1 + x)^x.
- Expansion of e.g.f. (1 - x)^x.A007114
Expansion of e.g.f. (1 - x)^x.
- Expansion of e.g.f. (1 - x - x^2)^x.A007115
Expansion of e.g.f. (1 - x - x^2)^x.
- Expansion of e.g.f. (1+x)^(exp(x)).A007116
Expansion of e.g.f. (1+x)^(exp(x)).
- a(0) = a(1) = 0; for n >= 2, a(n)*2^(n+2) + 1 is the smallest prime factor of the n-th Fermat number F(n) = 2^(2^n) + 1.A007117
a(0) = a(1) = 0; for n >= 2, a(n)*2^(n+2) + 1 is the smallest prime factor of the n-th Fermat number F(n) = 2^(2^n) + 1.
- Expansion of e.g.f. (1+x)^sin(x).A007118
Expansion of e.g.f. (1+x)^sin(x).
- Expansion of (1-x)^sin(x).A007119
Expansion of (1-x)^sin(x).
- Expansion of e.g.f. (1+x)^(1-x).A007120
Expansion of e.g.f. (1+x)^(1-x).
- Expansion of e.g.f. ( (1+x)^x )^x.A007121
Expansion of e.g.f. ( (1+x)^x )^x.
- Number of unlabeled identity connected unit interval graphs with n nodes.A007122
Number of unlabeled identity connected unit interval graphs with n nodes.
- Number of connected unit interval graphs with n nodes; also number of bracelets (turnover necklaces) with n black beads and n-1 white beads.A007123
Number of connected unit interval graphs with n nodes; also number of bracelets (turnover necklaces) with n black beads and n-1 white beads.
- Number of strength 1 Eulerian graphs with n nodes, 2 of odd degree.A007124
Number of strength 1 Eulerian graphs with n nodes, 2 of odd degree.
- Number of connected strength-1 Eulerian graphs with n nodes, 2 of odd degree.A007125
Number of connected strength-1 Eulerian graphs with n nodes, 2 of odd degree.
- Number of connected rooted strength 1 Eulerian graphs with n nodes.A007126
Number of connected rooted strength 1 Eulerian graphs with n nodes.
- Definition (1): Number of unlabeled strength-2 Eulerian graphs with n nodes.A007127
Definition (1): Number of unlabeled strength-2 Eulerian graphs with n nodes.
- Number of unlabeled strength 3 Eulerian graphs with n nodes.A007128
Number of unlabeled strength 3 Eulerian graphs with n nodes.
- Number of unlabeled strength 3 Eulerian graphs with n nodes, 2 of odd degree.A007129
Number of unlabeled strength 3 Eulerian graphs with n nodes, 2 of odd degree.
- Number of unlabeled rooted strength 3 Eulerian graphs with n nodes.A007130
Number of unlabeled rooted strength 3 Eulerian graphs with n nodes.
- Number of unlabeled connected strength 3 Eulerian graphs with n nodes.A007131
Number of unlabeled connected strength 3 Eulerian graphs with n nodes.
- Number of unlabeled connected strength 3 Eulerian graphs with n nodes, 2 of odd degree.A007132
Number of unlabeled connected strength 3 Eulerian graphs with n nodes, 2 of odd degree.
- Number of unlabeled rooted connected strength 3 Eulerian graphs with n nodes.A007133
Number of unlabeled rooted connected strength 3 Eulerian graphs with n nodes.
- Number of connected labeled chordal graphs (or triangulated graphs) with n nodes.A007134
Number of connected labeled chordal graphs (or triangulated graphs) with n nodes.
- Number of symmetry sites in all planted 1,3-trees with 2n nodes.A007135
Number of symmetry sites in all planted 1,3-trees with 2n nodes.
- Number of symmetry sites in all planted 3-trees with n nodes.A007136
Number of symmetry sites in all planted 3-trees with n nodes.
- Number of rooted maps with n edges on the projective plane.A007137
Number of rooted maps with n edges on the projective plane.
- Smallest primitive factor of 10^n - 1. Also smallest prime p such that 1/p has repeating decimal expansion of period n.A007138
Smallest primitive factor of 10^n - 1. Also smallest prime p such that 1/p has repeating decimal expansion of period n.
- Number of unlabeled bicolored bipartite graphs on 2n nodes having n nodes of each color with no edges between vertices of the same color and allowing the color classes to be interchanged.A007139
Number of unlabeled bicolored bipartite graphs on 2n nodes having n nodes of each color with no edges between vertices of the same color and allowing the color classes to be interchanged.
- Number of unlabeled bicolored graphs, with no isolated nodes, on 2n nodes having n nodes of each color and allowing the color classes to be interchanged.A007140
Number of unlabeled bicolored graphs, with no isolated nodes, on 2n nodes having n nodes of each color and allowing the color classes to be interchanged.
- E-trees with at most 2 colors.A007141
E-trees with at most 2 colors.
- E-trees with at most 3 colors.A007142
E-trees with at most 3 colors.
- E-trees with exactly 2 colors.A007143
E-trees with exactly 2 colors.
- E-trees with exactly 3 colors.A007144
E-trees with exactly 3 colors.
- Number of rooted bridgeless graphs with n nodes.A007145
Number of rooted bridgeless graphs with n nodes.
- Number of unlabeled simple connected bridgeless graphs with n nodes.A007146
Number of unlabeled simple connected bridgeless graphs with n nodes.
- Number of self-dual 2-colored necklaces with 2n beads.A007147
Number of self-dual 2-colored necklaces with 2n beads.
- Number of self-complementary 2-colored bracelets (turnover necklaces) with 2n beads.A007148
Number of self-complementary 2-colored bracelets (turnover necklaces) with 2n beads.
- 2-part of number of graphs on n nodes.A007149
2-part of number of graphs on n nodes.
- 2-part of number of tournaments on n nodes.A007150
2-part of number of tournaments on n nodes.
- Number of planted evolutionary trees of magnitude n.A007151
Number of planted evolutionary trees of magnitude n.
- Evolutionary trees of magnitude n.A007152
Evolutionary trees of magnitude n.
- Dedekind numbers: number of monotone Boolean functions or antichains of subsets of an n-set containing at least one nonempty set.A007153
Dedekind numbers: number of monotone Boolean functions or antichains of subsets of an n-set containing at least one nonempty set.
- Spectrum of the free Kleene algebra on n free variables.A007154
Spectrum of the free Kleene algebra on n free variables.
- (2^(2^n))*(3^(3^n - 2^n)).A007155
(2^(2^n))*(3^(3^n - 2^n)).
- Spectrum of a certain 3-element algebra.A007156
Spectrum of a certain 3-element algebra.
- Essentially n-ary operations in Kleene free algebra.A007157
Essentially n-ary operations in Kleene free algebra.
- Essentially n-ary operations in a certain 3-element algebra.A007158
Essentially n-ary operations in a certain 3-element algebra.
- Essentially n-ary operations in a certain 3-element algebra.A007159
Essentially n-ary operations in a certain 3-element algebra.