Question

Prove that the difference between numbers with the same sum of digits is a multiple of $9$.

score 231 · Answer 1 · 2021-03-22 15:27:54

231

Views

Prove that the difference between numbers with the same sum of digits is a multiple of $9$.

Published on 22 Mar 2021 - 15:27

score 166 · Answer 2 · 2021-03-27 20:59:09

166

Views

Finding the smallest $n$ such that $n^{2}$ ends with $00001$

Published on 27 Mar 2021 - 20:59

score 108 · Answer 3 · 2021-03-30 09:39:12

108

Views

How many prime numbers are there whose squares' decimal representation consist solely of integer squares?

Published on 30 Mar 2021 - 9:39

score 57 · Answer 4 · 2021-04-10 13:37:21

57

Views

Sum of the digits of powers of a number

Published on 10 Apr 2021 - 13:37

score 346 · Answer 5 · 2026-03-30 06:48:35

346

Views

Show that 1/p has period p-1 iff 10 is a primitive root mod p

Published on 30 Mar 2026 - 6:48

score 103 · Answer 6 · 2021-04-14 16:56:16

103

Views

More or less rigorous proof of the digital root formula

Published on 14 Apr 2021 - 16:56

score 64 · Answer 7 · 2021-04-19 23:19:56

64

Views

Is a binary sequence generated by repetition and subsequent digit flipping periodic?

Published on 19 Apr 2021 - 23:19

score 134 · Answer 8 · 2026-03-29 20:52:56

134

Views

Can we have nonstandard/transfinite "decimal" expansions?

Published on 29 Mar 2026 - 20:52

score 61 · Answer 9 · 2021-04-22 21:43:05

61

Views

A periodic decimal expansion sequence

Published on 22 Apr 2021 - 21:43

score 96 · Answer 10 · 2021-04-23 05:19:05

96

Views

Does $2^x$ not contain a 0 in decimal for almost all values of $x$

Published on 23 Apr 2021 - 5:19

score 115 · Answer 11 · 2021-05-11 05:59:06

115

Views

Is there any way to find the number of zeroes at the end of $n!$ for $n\ge5$?

Published on 11 May 2021 - 5:59

score 52 · Answer 12 · 2021-05-11 20:41:53

52

Views

Does parity of $f(a)$ and $f(a+1)$ are same whenever $a$ is even? Question related to sum of digits

Published on 11 May 2021 - 20:41

score 610 · Answer 13 · 2021-05-16 06:38:31

610

Views

Identifying an exact expression for a decimal value

Published on 16 May 2021 - 6:38

score 231 · Answer 14 · 2021-05-18 09:29:21

231

Views

Period length in the decimal expansion of fractions $1/n$

Published on 18 May 2021 - 9:29

score 349 · Answer 15 · 2021-06-06 01:24:27

349

Views

P-Adic Expansion of Rational Number (Reverse Direction)

Published on 06 Jun 2021 - 1:24

List Question

Prove that the difference between numbers with the same sum of digits is a multiple of $9$.

Finding the smallest $n$ such that $n^{2}$ ends with $00001$

How many prime numbers are there whose squares' decimal representation consist solely of integer squares?

Sum of the digits of powers of a number

Show that 1/p has period p-1 iff 10 is a primitive root mod p

More or less rigorous proof of the digital root formula

Is a binary sequence generated by repetition and subsequent digit flipping periodic?

Can we have nonstandard/transfinite "decimal" expansions?

A periodic decimal expansion sequence

Does $2^x$ not contain a 0 in decimal for almost all values of $x$

Is there any way to find the number of zeroes at the end of $n!$ for $n\ge5$?

Does parity of $f(a)$ and $f(a+1)$ are same whenever $a$ is even? Question related to sum of digits

Identifying an exact expression for a decimal value

Period length in the decimal expansion of fractions $1/n$

P-Adic Expansion of Rational Number (Reverse Direction)

Trending Questions

Popular # Hahtags

Popular Questions