Question

A phone number has seven digits and cannot begin with a 0. How many phone numbers contain the sequence 123?

score 192 · Answer 1 · 2023-08-12 13:26:18

192

Views

A phone number has seven digits and cannot begin with a 0. How many phone numbers contain the sequence 123?

Published on 12 Aug 2023 - 13:26

score 48 · Answer 2 · 2023-09-20 01:26:03

48

Views

A question about combinatorics involving words, patterns and overlaps

Published on 20 Sep 2023 - 1:26

score 120 · Answer 3 · 2026-02-23 12:17:40

120

Views

What's the minimum guaranteed substring match between a binary string and a chosen rotation?

Published on 23 Feb 2026 - 12:17

score 117 · Answer 4 · 2026-03-25 14:00:39

117

Views

Which hyperoperations produce a "prefix-complete" sequence?

Published on 25 Mar 2026 - 14:00

score 398 · Answer 5 · 2023-11-02 06:46:16

398

Views

Number of words with 8 letters using an alphabet of 3 consonants and 2 vowels with constraints

Published on 02 Nov 2023 - 6:46

score 222 · Answer 6 · 2023-11-21 17:02:42

222

Views

How many binary strings of length 10 are there that don't contain either of the substrings 101 or 010?

Published on 21 Nov 2023 - 17:02

score 15 · Answer 7 · 2026-03-26 19:02:06

15

Views

Separating a primitive word of $A^$ from its proper prefixes by a monoid morphism from $A^$ to $\mathbb Z$.

Published on 26 Mar 2026 - 19:02

score 90 · Answer 8 · 2023-12-15 06:03:46

90

Views

Discrete Math Strings

Published on 15 Dec 2023 - 6:03

score 18 · Answer 9 · 2026-02-23 08:41:13

18

Views

Seeking Formalization or Verification of an Inequality Involving Sums and Products

Published on 23 Feb 2026 - 8:41

score 90 · Answer 10 · 2024-01-10 12:48:50

90

Views

Expanding series to obtain desired words using generating functions

Published on 10 Jan 2024 - 12:48

score 23 · Answer 11 · 2024-01-15 21:09:14

23

Views

Why does this example not break avoidability?

Published on 15 Jan 2024 - 21:09

score 32 · Answer 12 · 2024-01-20 23:53:44

32

Views

Words that are "raised above" the decreasing word $(n)(n-1) \cdots (2)(1)$.

Published on 20 Jan 2024 - 23:53

score 38 · Answer 13 · 2024-02-02 03:12:24

38

Views

Is $2$-avoidability determinable?

Published on 02 Feb 2024 - 3:12

score 101 · Answer 14 · 2024-02-20 07:57:00

101

Views

Combinatorial problem about finding equidistant words

Published on 20 Feb 2024 - 7:57

score 87 · Answer 15 · 2024-02-25 16:01:39

87

Views

Prove a string can be rearranged such that no character repeats

Published on 25 Feb 2024 - 16:01

List Question

A phone number has seven digits and cannot begin with a 0. How many phone numbers contain the sequence 123?

A question about combinatorics involving words, patterns and overlaps

What's the minimum guaranteed substring match between a binary string and a chosen rotation?

Which hyperoperations produce a "prefix-complete" sequence?

Number of words with 8 letters using an alphabet of 3 consonants and 2 vowels with constraints

How many binary strings of length 10 are there that don't contain either of the substrings 101 or 010?

Separating a primitive word of $A^$ from its proper prefixes by a monoid morphism from $A^$ to $\mathbb Z$.

Discrete Math Strings

Seeking Formalization or Verification of an Inequality Involving Sums and Products

Expanding series to obtain desired words using generating functions

Why does this example not break avoidability?

Words that are "raised above" the decreasing word $(n)(n-1) \cdots (2)(1)$.

Is $2$-avoidability determinable?

Combinatorial problem about finding equidistant words

Prove a string can be rearranged such that no character repeats

Trending Questions

Popular # Hahtags

Popular Questions