# Questions tagged [oeis]

The acronym OEIS stands for the On-Line Encyclopedia of Integer Sequences, a well-known database of sequences of integers. It can be used for questions where this database is (or might be) relevant, mainly questions about particular sequences of integers. This tag is typically used in combination with other tags to make the scope of the question more precise; common examples of such tags include the top-level tags co.combinatorics and nt.number-theory.

**8**

**1**answer

### Conjecture by Ekedahl on Weyl groups and Abelian varieties

**2**

**2**answers

### Positions in the Wythoff array

**12**

**1**answer

### On the iterated automorphism groups of the cyclic groups

**4**

**0**answers

### Hypergraphs with only disjoint perfect matchings

**4**

**1**answer

### Difference of two integer sequences: all zeros and ones?

**12**

**2**answers

### A reformulation of Erdős conjecture on arithmetic progressions

**3**

**0**answers

### Guises of the refined Eulerian numbers, generated by tangent vectors (OEIS A145271)

**6**

**0**answers

### Guises of the Noncrossing Partitions (NCPs)

**9**

**0**answers

### On the first sequence without collinear triple

**45**

**0**answers

### On the first sequence without triple in arithmetic progression

**3**

**3**answers

### Expansions of iterated, or nested, derivatives, or vectors--conjectured matrix computation

**8**

**2**answers

### Сlosed formula for $(g\partial)^n$

**6**

**1**answer

### Are there infinitely many insipid numbers?

**2**

**1**answer

### The sporadic numbers

**8**

**4**answers

### Simple-looking sequences $A$ and $B$ defined by a complementary equation

**7**

**1**answer

### Number of numbers in $n$th difference sequence

**11**

**1**answer

### Integrals of power towers

**25**

**0**answers

### A sequence potentially consisting of only integers

**8**

**1**answer

### Reference for Kakutani result on power sum bases of symmetric functions

**5**

**0**answers

### Dirichlet eta function and Stirling Permutations

**4**

**0**answers

### Conjecture on tilting modules for an Auslander algebra

**6**

**1**answer

### Why is the number of Hamiltonian Cycles of n-octahedron equivalent to the number of Perfect Matching in specific family of Graphs?

**25**

**3**answers

### Advanced software for OEIS?

**0**

**1**answer

### Ordinary Generating Function for OEIS A056296?

**30**

**7**answers

### Examples of integer sequences coincidences

**2**

**1**answer

### Counting particular Dyck paths

**12**

**1**answer

### Ramanujan's Lost Notebook page 1 first equation and OEIS sequence A260195

**1**

**2**answers

### Linear Extension of the $n\times n$ lattice

**1**

**1**answer

### OEIS Sequence A002846 and properties of matrix inverses

**0**

**0**answers

### Conjectured congruence $A048852(n-1) \equiv p_n - p_{n-1} \pmod{4}$

**8**

**4**answers

### Computationally challenging integer sequences

**2**

**0**answers

### Link of a power series by the Bernoullis for a Riccati equation to zonotopes?

**2**

**0**answers

### Claim in OEIS will give some results about Legendre's and Brocard's conjectures

**0**

**1**answer

### Any results on $\gcd(N^2, D(N^2))$ where $N^2$ is deficient and $D(N^2)$ is the deficiency of $N^2$?

**7**

**0**answers

### Increasing derivatives of recursively defined polynomials

**2**

**1**answer

### Relating face polytopes of permutohedra to integer partitions

**3**

**0**answers

### First to note/document the relation between permutohedra and multiplicative inversion

**7**

**1**answer

### Frankl's conjecture and Oeis sequence A188163

**4**

**1**answer

### Can we always attain another prime via inserting digits between the digits of a fixed prime?

**5**

**1**answer

### Up to $2000$, $A145722(n-1) \equiv \sigma(4n-3) \pmod{5}$

**7**

**0**answers

### Has anyone seen these binary trees (Catalan-type related to the Gegenbauer polynomials and Motzkin paths)?

**8**

**2**answers

### Asymptotics of product of Euler's totient function (A001088)?

**7**

**1**answer

### Another formula for Bell numbers

**3**

**1**answer

### Upper bound for OEIS A076689 “Smallest k such that k*p#+1 is prime”?

**18**

**10**answers

### Combinatorial Databases

**22**

**1**answer

### Wrong asymptotics of OEIS A000607 (number of partitions of an integer in prime parts)?

**12**

**4**answers

### Ordinary Generating Function for Bell Numbers

**5**

**2**answers

### Are all counterexamples of OEIS A226181 both Poulet numbers and Proth numbers?

**41**

**2**answers

### Numbers that are generic w.r.t. exponentiation

**23**

**1**answer