Sequences
392,541 sequences
- Gaussian binomial coefficient [n, 5] for q = 2.A006110
Gaussian binomial coefficient [n, 5] for q = 2.
- Gaussian binomial coefficient [ n,2 ] for q=5.A006111
Gaussian binomial coefficient [ n,2 ] for q=5.
- Gaussian binomial coefficient [ n,3 ] for q = 5.A006112
Gaussian binomial coefficient [ n,3 ] for q = 5.
- Gaussian binomial coefficient [ n,4 ] for q = 5.A006113
Gaussian binomial coefficient [ n,4 ] for q = 5.
- Gaussian binomial coefficient [ 2n,n ] for q=5.A006114
Gaussian binomial coefficient [ 2n,n ] for q=5.
- Gaussian binomial coefficient [ n,n/2 ] for q=5.A006115
Gaussian binomial coefficient [ n,n/2 ] for q=5.
- Sum of Gaussian binomial coefficients [n,k] for q=2 and k=0..n.A006116
Sum of Gaussian binomial coefficients [n,k] for q=2 and k=0..n.
- Sum of Gaussian binomial coefficients [ n,k ] for q=3.A006117
Sum of Gaussian binomial coefficients [ n,k ] for q=3.
- Sum of Gaussian binomial coefficients [ n,k ] for q=4.A006118
Sum of Gaussian binomial coefficients [ n,k ] for q=4.
- Sum of Gaussian binomial coefficients [ n,k ] for q=5.A006119
Sum of Gaussian binomial coefficients [ n,k ] for q=5.
- Sum of Gaussian binomial coefficients [ n,k ] for q=6.A006120
Sum of Gaussian binomial coefficients [ n,k ] for q=6.
- Sum of Gaussian binomial coefficients [ n,k ] for q=7.A006121
Sum of Gaussian binomial coefficients [ n,k ] for q=7.
- Sum of Gaussian binomial coefficients [ n,k ] for q=8.A006122
Sum of Gaussian binomial coefficients [ n,k ] for q=8.
- Erroneous version of A000085.A006123
Erroneous version of A000085.
- a(n) = 3 + n/2 + 7*n^2/2.A006124
a(n) = 3 + n/2 + 7*n^2/2.
- a(n) = 2^(n*(n-1)/2).A006125
a(n) = 2^(n*(n-1)/2).
- Number of hierarchical models on n labeled factors or variables with linear terms forced. Also number of antichain covers of a labeled n-set.A006126
Number of hierarchical models on n labeled factors or variables with linear terms forced. Also number of antichain covers of a labeled n-set.
- a(n) = 2^n + n.A006127
a(n) = 2^n + n.
- Total number of parts in all partitions of n. Also, sum of largest parts of all partitions of n.A006128
Total number of parts in all partitions of n. Also, sum of largest parts of all partitions of n.
- a(0), a(1), a(2), ... satisfy Sum_{k=0..n} a(k)*binomial(n,k) = 2^binomial(n,2), for n >= 0.A006129
a(0), a(1), a(2), ... satisfy Sum_{k=0..n} a(k)*binomial(n,k) = 2^binomial(n,2), for n >= 0.
- a(n) = a(n-1) + 3*a(n-2) for n > 1, a(0) = a(1) = 1.A006130
a(n) = a(n-1) + 3*a(n-2) for n > 1, a(0) = a(1) = 1.
- a(n) = a(n-1) + 4*a(n-2), a(0) = a(1) = 1.A006131
a(n) = a(n-1) + 4*a(n-2), a(0) = a(1) = 1.
- Related to representations as sums of Fibonacci numbers.A006132
Related to representations as sums of Fibonacci numbers.
- Related to representations as sums of Fibonacci numbers.A006133
Related to representations as sums of Fibonacci numbers.
- a(n) = Sum_{k=0..n} binomial(2*k,k).A006134
a(n) = Sum_{k=0..n} binomial(2*k,k).
- T(n+2,2) from table A045912 of characteristic polynomial of negative Pascal matrix.A006135
T(n+2,2) from table A045912 of characteristic polynomial of negative Pascal matrix.
- T(n+3,3) from table A045912 of characteristic polynomial of negative Pascal matrix.A006136
T(n+3,3) from table A045912 of characteristic polynomial of negative Pascal matrix.
- a(n) = 1 + n/2 + 9*n^2/2.A006137
a(n) = 1 + n/2 + 9*n^2/2.
- a(n) = a(n-1) + 3*a(n-2).A006138
a(n) = a(n-1) + 3*a(n-2).
- n*a(n) = 2*(2*n-1)*a(n-1) + 4*(n-1)*a(n-2) with a(0) = 1.A006139
n*a(n) = 2*(2*n-1)*a(n-1) + 4*(n-1)*a(n-2) with a(0) = 1.
- Erroneous version of A003406.A006140
Erroneous version of A003406.
- Number of integer partitions of n whose smallest part is equal to the number of parts.A006141
Number of integer partitions of n whose smallest part is equal to the number of parts.
- Number of certain self-avoiding walks with n steps on square lattice (see reference for precise definition).A006142
Number of certain self-avoiding walks with n steps on square lattice (see reference for precise definition).
- Number of certain self-avoiding walks with n steps on square lattice (see reference for precise definition).A006143
Number of certain self-avoiding walks with n steps on square lattice (see reference for precise definition).
- Number of certain self-avoiding walks with n steps on square lattice (see reference for precise definition).A006144
Number of certain self-avoiding walks with n steps on square lattice (see reference for precise definition).
- Ruth-Aaron numbers (1): sum of prime divisors of n = sum of prime divisors of n+1.A006145
Ruth-Aaron numbers (1): sum of prime divisors of n = sum of prime divisors of n+1.
- Sums of prime divisors of Ruth-Aaron numbers (A006145).A006146
Sums of prime divisors of Ruth-Aaron numbers (A006145).
- Reversion of Ramanujan numbers.A006147
Reversion of Ramanujan numbers.
- Number of 4 X n binary matrices up to row and column permutations.A006148
Number of 4 X n binary matrices up to row and column permutations.
- Number of 3-tuples (p_1, p_2, p_3) of Dyck paths of semilength n, such that each p_i is never below p_{i-1}.A006149
Number of 3-tuples (p_1, p_2, p_3) of Dyck paths of semilength n, such that each p_i is never below p_{i-1}.
- Number of 4-tuples (p_1, p_2, ..., p_4) of Dyck paths of semilength n, such that each p_i is never below p_{i-1}.A006150
Number of 4-tuples (p_1, p_2, ..., p_4) of Dyck paths of semilength n, such that each p_i is never below p_{i-1}.
- Number of 5-tuples (p_1, p_2, ..., p_5) of Dyck paths of semilength n, such that each p_i is never below p_{i-1}.A006151
Number of 5-tuples (p_1, p_2, ..., p_5) of Dyck paths of semilength n, such that each p_i is never below p_{i-1}.
- Exponential generating function x*exp(x/(1-x)).A006152
Exponential generating function x*exp(x/(1-x)).
- E.g.f.: 1/(1-x*exp(x)).A006153
E.g.f.: 1/(1-x*exp(x)).
- Number of labeled ordered partitions of an n-set into odd parts.A006154
Number of labeled ordered partitions of an n-set into odd parts.
- Expansion of e.g.f.: 1/(2-x-exp(x)).A006155
Expansion of e.g.f.: 1/(2-x-exp(x)).
- Number of ternary squarefree words of length n.A006156
Number of ternary squarefree words of length n.
- a(n+1) = (n-1)*a(n) + n*n!.A006157
a(n+1) = (n-1)*a(n) + n*n!.
- a(n) = a(a(n-3)) + a(n-a(n-3)).A006158
a(n) = a(a(n-3)) + a(n-a(n-3)).
- a(n)=a(a(n-4))+a(n-a(n-4)).A006159
a(n)=a(a(n-4))+a(n-a(n-4)).