MathDB

For every sequence

(x_1, x_2, \ldots, x_n)

of non-zero natural prime numbers,

\{1, 2, \ldots, n\}

arranged in any order, denote by

f(s)

the sum of absolute values of the differences between two consecutive members of

s.

Find the maximum value of

f(s)

where

s

runs through the set of all such sequences, i.e. for all sequences

s

with the given properties.

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