Talk:First perfect square in base n with n unique digits: Difference between revisions
Talk:First perfect square in base n with n unique digits (view source)
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, 3 years agoThundergnat moved page Talk:First perfect square in base N with N unique digits to Talk:First perfect square in base n with n unique digits: Follow normal task title capitalization policy
m (→any ideas of optimizations ?: speed up adding to base x <127) |
Thundergnat (talk | contribs) m (Thundergnat moved page Talk:First perfect square in base N with N unique digits to Talk:First perfect square in base n with n unique digits: Follow normal task title capitalization policy) |
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==Incorrect Example==
Base 3 : Num 11 sqr 121
--LambertDW 18:28, 2 March 2020 (UTC)
Hmm. I am the original task author, but that list was added by someone else well after the task was written. You are correct though, that is wrong. --[[User:Thundergnat|Thundergnat]] ([[User talk:Thundergnat|talk]]) 23:19, 2 March 2020 (UTC)
==Leading zeros ?==
Line 90 ⟶ 96:
= $0901 -> 91</pre>
: it speeds up additions by a factor of 3, but checking the used digits takes ~ 40% of runtime - 60%/3+40% = 60%
:: think of base 10 and the square of the last 2-digits. of a number.If the last 2 digits of the square are the same you need not to test the complete number.
<pre> 0 10 12 20 30 38 40 50 60 62 70 80 88 90
86 of 100 are left over not that impressive</pre>
::using more digits increases the proportion even more 4 digits -> 4660 of 10000 are left over to test.
::but 4 digits to base 37 lead to 1542240 of 1874161 need to be checked.Not that useful.
==Space compression and proof ?==
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