Newbetuts

Last digits of power towers $7$, $7^7$, $7^{7^7}$, $7^{7^{7^7}}$, ... don't change, and generalisation

Mysterious $10$-digit numbers, how many of such exist?

Multiples of $999$ have digit sum $\geq 27$

Cyclic numbers are characterized by the reciprocals of full reptend primes?

Find The Last 3 digits of the number $2003^{2002^{2001}}$

Recurring decimal expansion of $\frac17$

Variation of the Kempner series – convergence of series $\sum\frac{1}{n}$ where $9$ is not a digit of $1/n$.

Is $0.248163264128…$ a transcendental number?

How can I explain $0.999\ldots=1$? [duplicate]

Calculate the 146th digit after the decimal point of $ \frac{1}{293} $

Primes with digits only 1

Do there exist numbers normal in every base except for one?

Divisibility by $9$

Are there any bases which represent all rationals in a finite number of digits?

Multiplication of doubly-infinite decimal numbers

How can you show by hand that $ e^{-1/e} < \ln(2) $?

Numbers having in decimal representation no common digits with all their proper divisors

New posts in decimal-expansion

Doubling sequences of the cyclic decimal parts of the fraction numbers

Does it make any sense to prove $0.999\ldots=1$?

Prove there are no hidden messages in Pi

Last digits of power towers $7$, $7^7$, $7^{7^7}$, $7^{7^{7^7}}$, ... don't change, and generalisation

Mysterious $10$-digit numbers, how many of such exist?

Multiples of $999$ have digit sum $\geq 27$

Cyclic numbers are characterized by the reciprocals of full reptend primes?

Find The Last 3 digits of the number $2003^{2002^{2001}}$

Recurring decimal expansion of $\frac17$

Variation of the Kempner series – convergence of series $\sum\frac{1}{n}$ where $9$ is not a digit of $1/n$.

Is $0.248163264128…$ a transcendental number?

How can I explain $0.999\ldots=1$? [duplicate]

Calculate the 146th digit after the decimal point of $ \frac{1}{293} $

Primes with digits only 1

Do there exist numbers normal in every base except for one?

Divisibility by $9$

Are there any bases which represent all rationals in a finite number of digits?

Multiplication of doubly-infinite decimal numbers

How can you show by hand that $ e^{-1/e} < \ln(2) $?

Numbers having in decimal representation no common digits with all their proper divisors