From 2019 to digits
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Is it possible to obtain the digits from 0 to 9 starting from 2019 and using its digits in the same order, together with the usual operations +, *, -, /, concatenation of digits, and the less usual operators ^, !, sqrt(), int()? For example, 1 = 20-19. Unary minus is allowed too.
I manage to use only basic operations and elevation to a power for all digits except 4 and 5, but maybe somebody will do better!
arithmetic
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add a comment |
$begingroup$
Is it possible to obtain the digits from 0 to 9 starting from 2019 and using its digits in the same order, together with the usual operations +, *, -, /, concatenation of digits, and the less usual operators ^, !, sqrt(), int()? For example, 1 = 20-19. Unary minus is allowed too.
I manage to use only basic operations and elevation to a power for all digits except 4 and 5, but maybe somebody will do better!
arithmetic
$endgroup$
add a comment |
$begingroup$
Is it possible to obtain the digits from 0 to 9 starting from 2019 and using its digits in the same order, together with the usual operations +, *, -, /, concatenation of digits, and the less usual operators ^, !, sqrt(), int()? For example, 1 = 20-19. Unary minus is allowed too.
I manage to use only basic operations and elevation to a power for all digits except 4 and 5, but maybe somebody will do better!
arithmetic
$endgroup$
Is it possible to obtain the digits from 0 to 9 starting from 2019 and using its digits in the same order, together with the usual operations +, *, -, /, concatenation of digits, and the less usual operators ^, !, sqrt(), int()? For example, 1 = 20-19. Unary minus is allowed too.
I manage to use only basic operations and elevation to a power for all digits except 4 and 5, but maybe somebody will do better!
arithmetic
arithmetic
asked Dec 23 '18 at 20:45
maumau
1,0041233
1,0041233
add a comment |
add a comment |
1 Answer
1
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$begingroup$
$0 = 2 cdot 0 cdot 1 cdot 9$
$1 = 20 - 19$
$2 = 2^0 + 1^9$
$3 = 2+0+1^9$
$4 = lfloor sqrt{20} rfloor + lfloor 1/9 rfloor$
$5 = 2 + 0 cdot 1 + sqrt{9}$
$6 = -(2+0+1) + 9$
$7 = -(2+0 cdot 1) + 9$
$8 = -(2 cdot 0 + 1) + 9$
$9 = -(2 cdot 0 cdot 1) + 9$
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1
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@deepthought Fixed.
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– Display name
Dec 23 '18 at 21:29
3
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Nice! 4 may also be $2cdot 0 + 1 + sqrt 9$
$endgroup$
– mau
Dec 23 '18 at 21:48
1
$begingroup$
A few more for 4 and 5: $lfloorsqrt{sqrt{20times19}}rfloor=4$, $lceilsqrt{sqrt{20times19}}rceil=5$ , $lceilsqrt{2+0+1+9}rceil=4$ , $lfloorsqrt{2+0+19}rfloor=4$ , $lceilsqrt{2+0+19}rceil=5$
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– JonMark Perry
Dec 23 '18 at 22:02
1
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and $lfloorsqrt{201}rfloor-9=5$
$endgroup$
– JonMark Perry
Dec 23 '18 at 22:05
1
$begingroup$
Fun fact: $-lfloor -x rfloor = lceil x rceil.$
$endgroup$
– Display name
Dec 23 '18 at 22:55
|
show 1 more comment
Your Answer
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1 Answer
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oldest
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1 Answer
1
active
oldest
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active
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active
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votes
$begingroup$
$0 = 2 cdot 0 cdot 1 cdot 9$
$1 = 20 - 19$
$2 = 2^0 + 1^9$
$3 = 2+0+1^9$
$4 = lfloor sqrt{20} rfloor + lfloor 1/9 rfloor$
$5 = 2 + 0 cdot 1 + sqrt{9}$
$6 = -(2+0+1) + 9$
$7 = -(2+0 cdot 1) + 9$
$8 = -(2 cdot 0 + 1) + 9$
$9 = -(2 cdot 0 cdot 1) + 9$
$endgroup$
1
$begingroup$
@deepthought Fixed.
$endgroup$
– Display name
Dec 23 '18 at 21:29
3
$begingroup$
Nice! 4 may also be $2cdot 0 + 1 + sqrt 9$
$endgroup$
– mau
Dec 23 '18 at 21:48
1
$begingroup$
A few more for 4 and 5: $lfloorsqrt{sqrt{20times19}}rfloor=4$, $lceilsqrt{sqrt{20times19}}rceil=5$ , $lceilsqrt{2+0+1+9}rceil=4$ , $lfloorsqrt{2+0+19}rfloor=4$ , $lceilsqrt{2+0+19}rceil=5$
$endgroup$
– JonMark Perry
Dec 23 '18 at 22:02
1
$begingroup$
and $lfloorsqrt{201}rfloor-9=5$
$endgroup$
– JonMark Perry
Dec 23 '18 at 22:05
1
$begingroup$
Fun fact: $-lfloor -x rfloor = lceil x rceil.$
$endgroup$
– Display name
Dec 23 '18 at 22:55
|
show 1 more comment
$begingroup$
$0 = 2 cdot 0 cdot 1 cdot 9$
$1 = 20 - 19$
$2 = 2^0 + 1^9$
$3 = 2+0+1^9$
$4 = lfloor sqrt{20} rfloor + lfloor 1/9 rfloor$
$5 = 2 + 0 cdot 1 + sqrt{9}$
$6 = -(2+0+1) + 9$
$7 = -(2+0 cdot 1) + 9$
$8 = -(2 cdot 0 + 1) + 9$
$9 = -(2 cdot 0 cdot 1) + 9$
$endgroup$
1
$begingroup$
@deepthought Fixed.
$endgroup$
– Display name
Dec 23 '18 at 21:29
3
$begingroup$
Nice! 4 may also be $2cdot 0 + 1 + sqrt 9$
$endgroup$
– mau
Dec 23 '18 at 21:48
1
$begingroup$
A few more for 4 and 5: $lfloorsqrt{sqrt{20times19}}rfloor=4$, $lceilsqrt{sqrt{20times19}}rceil=5$ , $lceilsqrt{2+0+1+9}rceil=4$ , $lfloorsqrt{2+0+19}rfloor=4$ , $lceilsqrt{2+0+19}rceil=5$
$endgroup$
– JonMark Perry
Dec 23 '18 at 22:02
1
$begingroup$
and $lfloorsqrt{201}rfloor-9=5$
$endgroup$
– JonMark Perry
Dec 23 '18 at 22:05
1
$begingroup$
Fun fact: $-lfloor -x rfloor = lceil x rceil.$
$endgroup$
– Display name
Dec 23 '18 at 22:55
|
show 1 more comment
$begingroup$
$0 = 2 cdot 0 cdot 1 cdot 9$
$1 = 20 - 19$
$2 = 2^0 + 1^9$
$3 = 2+0+1^9$
$4 = lfloor sqrt{20} rfloor + lfloor 1/9 rfloor$
$5 = 2 + 0 cdot 1 + sqrt{9}$
$6 = -(2+0+1) + 9$
$7 = -(2+0 cdot 1) + 9$
$8 = -(2 cdot 0 + 1) + 9$
$9 = -(2 cdot 0 cdot 1) + 9$
$endgroup$
$0 = 2 cdot 0 cdot 1 cdot 9$
$1 = 20 - 19$
$2 = 2^0 + 1^9$
$3 = 2+0+1^9$
$4 = lfloor sqrt{20} rfloor + lfloor 1/9 rfloor$
$5 = 2 + 0 cdot 1 + sqrt{9}$
$6 = -(2+0+1) + 9$
$7 = -(2+0 cdot 1) + 9$
$8 = -(2 cdot 0 + 1) + 9$
$9 = -(2 cdot 0 cdot 1) + 9$
edited Dec 24 '18 at 5:20
S. M.
953419
953419
answered Dec 23 '18 at 21:13
Display nameDisplay name
1,000217
1,000217
1
$begingroup$
@deepthought Fixed.
$endgroup$
– Display name
Dec 23 '18 at 21:29
3
$begingroup$
Nice! 4 may also be $2cdot 0 + 1 + sqrt 9$
$endgroup$
– mau
Dec 23 '18 at 21:48
1
$begingroup$
A few more for 4 and 5: $lfloorsqrt{sqrt{20times19}}rfloor=4$, $lceilsqrt{sqrt{20times19}}rceil=5$ , $lceilsqrt{2+0+1+9}rceil=4$ , $lfloorsqrt{2+0+19}rfloor=4$ , $lceilsqrt{2+0+19}rceil=5$
$endgroup$
– JonMark Perry
Dec 23 '18 at 22:02
1
$begingroup$
and $lfloorsqrt{201}rfloor-9=5$
$endgroup$
– JonMark Perry
Dec 23 '18 at 22:05
1
$begingroup$
Fun fact: $-lfloor -x rfloor = lceil x rceil.$
$endgroup$
– Display name
Dec 23 '18 at 22:55
|
show 1 more comment
1
$begingroup$
@deepthought Fixed.
$endgroup$
– Display name
Dec 23 '18 at 21:29
3
$begingroup$
Nice! 4 may also be $2cdot 0 + 1 + sqrt 9$
$endgroup$
– mau
Dec 23 '18 at 21:48
1
$begingroup$
A few more for 4 and 5: $lfloorsqrt{sqrt{20times19}}rfloor=4$, $lceilsqrt{sqrt{20times19}}rceil=5$ , $lceilsqrt{2+0+1+9}rceil=4$ , $lfloorsqrt{2+0+19}rfloor=4$ , $lceilsqrt{2+0+19}rceil=5$
$endgroup$
– JonMark Perry
Dec 23 '18 at 22:02
1
$begingroup$
and $lfloorsqrt{201}rfloor-9=5$
$endgroup$
– JonMark Perry
Dec 23 '18 at 22:05
1
$begingroup$
Fun fact: $-lfloor -x rfloor = lceil x rceil.$
$endgroup$
– Display name
Dec 23 '18 at 22:55
1
1
$begingroup$
@deepthought Fixed.
$endgroup$
– Display name
Dec 23 '18 at 21:29
$begingroup$
@deepthought Fixed.
$endgroup$
– Display name
Dec 23 '18 at 21:29
3
3
$begingroup$
Nice! 4 may also be $2cdot 0 + 1 + sqrt 9$
$endgroup$
– mau
Dec 23 '18 at 21:48
$begingroup$
Nice! 4 may also be $2cdot 0 + 1 + sqrt 9$
$endgroup$
– mau
Dec 23 '18 at 21:48
1
1
$begingroup$
A few more for 4 and 5: $lfloorsqrt{sqrt{20times19}}rfloor=4$, $lceilsqrt{sqrt{20times19}}rceil=5$ , $lceilsqrt{2+0+1+9}rceil=4$ , $lfloorsqrt{2+0+19}rfloor=4$ , $lceilsqrt{2+0+19}rceil=5$
$endgroup$
– JonMark Perry
Dec 23 '18 at 22:02
$begingroup$
A few more for 4 and 5: $lfloorsqrt{sqrt{20times19}}rfloor=4$, $lceilsqrt{sqrt{20times19}}rceil=5$ , $lceilsqrt{2+0+1+9}rceil=4$ , $lfloorsqrt{2+0+19}rfloor=4$ , $lceilsqrt{2+0+19}rceil=5$
$endgroup$
– JonMark Perry
Dec 23 '18 at 22:02
1
1
$begingroup$
and $lfloorsqrt{201}rfloor-9=5$
$endgroup$
– JonMark Perry
Dec 23 '18 at 22:05
$begingroup$
and $lfloorsqrt{201}rfloor-9=5$
$endgroup$
– JonMark Perry
Dec 23 '18 at 22:05
1
1
$begingroup$
Fun fact: $-lfloor -x rfloor = lceil x rceil.$
$endgroup$
– Display name
Dec 23 '18 at 22:55
$begingroup$
Fun fact: $-lfloor -x rfloor = lceil x rceil.$
$endgroup$
– Display name
Dec 23 '18 at 22:55
|
show 1 more comment
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