Is it a doubling sequence? A doubling sequence is an array of numbers where each subsequent number is at least twice the previous number.
Given an ordered list of numbers, determine if the numbers in the list (\$n_{x}\$) have the property that:
\$n_1 \times 2 \le n_2\$
\$n_2 \times 2 \le n_3\ ...\$
and so on until reaching the end of the list.
Input
A list of two or more numbers.
Output
Any distinct True or False value.
Examples:
[10,20,30] -&gt; False
[10,20,40] -&gt; True
[1,2,3] -&gt; False
[1,2,4] -&gt; True
[1,2,10] -&gt; True
[1,1] -&gt; False
[10,1] -&gt; False
R, 27 26 bytes



all(diff(log2(scan()))&gt;=1)


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