New posts in decimal-expansion

Show that there are infinitely many powers of two starting with the digit 7 [duplicate]

abstract-algebra number-theory elementary-number-theory contest-math decimal-expansion

What is the *middle* digit of $3^{100000}$?

number-theory exponentiation computational-complexity decimal-expansion

Is $2^{16} = 65536$ the only power of $2$ that has no digit which is a power of $2$ in base-$10$?

number-theory recreational-mathematics exponentiation decimal-expansion

How do we prove that $\lfloor0.999\cdots\rfloor = \lfloor 1 \rfloor$?

real-analysis examples-counterexamples ceiling-and-floor-functions decimal-expansion

Numbers $n$ such that the digit sums of $n, n^2,\cdots,n^k$ coincide.

number-theory decimal-expansion

The last two digits of $9^{9^9}$

elementary-number-theory modular-arithmetic exponentiation decimal-expansion

How are the known digits of $\pi$ guaranteed?

pi decimal-expansion

Is sum of digits of $3^{1000}$ divisible by $7$?

elementary-number-theory modular-arithmetic arithmetic divisibility decimal-expansion

How many zeroes are in 100!

factorial decimal-expansion

How come the number $N!$ can terminate in exactly $1,2,3,4,$ or $6$ zeroes but never $5$ zeroes? [duplicate]

elementary-number-theory divisibility factorial decimal-expansion

last two digits of $14^{5532}$?

elementary-number-theory modular-arithmetic exponentiation decimal-expansion

Find the last two digits of $ 7^{81} ?$

elementary-number-theory modular-arithmetic decimal-expansion

Extending prime numbers digit by digit while retaining primality

elementary-number-theory prime-numbers recreational-mathematics decimal-expansion

Call a number "holy" if it contains no $666$ in its decimal expansion. Are there infinitely many holy powers of $2$?

sequences-and-series decimal-expansion

Is $0.1010010001000010000010000001 \ldots$ transcendental?

transcendental-numbers decimal-expansion

Why does the first 100,000 zeroes of the Riemann Zeta function have double-digit sequence count discontinuities at 00,11,22,33,44,55,66,77,88,99?

riemann-zeta decimal-expansion

What is the smallest positive multiple of 450 whose digits are all zeroes and ones?

elementary-number-theory divisibility number-systems decimal-expansion

Prove that none of $\{11, 111, 1111,\dots \}$ is the perfect square of an integer

elementary-number-theory decimal-expansion square-numbers repunit-numbers

Is $6.12345678910111213141516171819202122\ldots$ transcendental?

decimal-expansion transcendental-numbers

Does $1.0000000000\cdots 1$ with an infinite number of $0$ in it exist?

calculus limits real-numbers infinity decimal-expansion