This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A078265 #18 Jun 25 2025 21:24:30
%S A078265 1,15,207,2544,30091,347096,3931343,43906441,484912312,5306957044
%N A078265 Integer part of the geometric mean of all the distinct numbers formed by permuting the digits of concatenation of numbers from 1 to n.
%C A078265 For n < 10 there are n! distinct numbers.
%e A078265 a(3) = floor((123*132*213*231*312*321)^(1/6)) = floor(207.581...) = 207.
%e A078265 a(4) = floor((1234*1243*1324*1342*1423*1432*...*4312*4321)^(1/24)) = floor(2544.967...) = 2544.
%t A078265 a[n_] := Floor[ (Times @@ FromDigits /@ Permutations[Range[n]])^(1/n!) ]; Table[a[n], {n, 1, 10}] (* _Ryan Propper_, Jul 21 2006 *)
%Y A078265 Cf. A071268, A078266.
%K A078265 base,more,nonn
%O A078265 1,2
%A A078265 _Amarnath Murthy_, Nov 24 2002
%E A078265 More terms from _Ryan Propper_, Jul 21 2006