A180073 - OEIS

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A180073

Number of permutations of 1..n with the sum of squared adjacent differences < (n-1)*n*(n+1)/6.

%I #10 Nov 16 2023 07:15:44

%S 0,2,12,56,344,2486,19936,179772,1800566,19867748,238718608,

%T 3105919304,43474755484,652732780048,10446585803476,177631436657888

%N Number of permutations of 1..n with the sum of squared adjacent differences < (n-1)*n*(n+1)/6.

%Y Cf. A000292, A180072.

%K nonn

%O 2,2

%A _R. H. Hardin_, Aug 09 2010

%E a(14) from _Donovan Johnson_, Oct 11 2010

%E a(15)-a(17) from _Martin Ehrenstein_, Nov 16 2023