Number of permutations of 1..n with sum (i-p(i))^2 < n*(n-1)/2.

A179265

Number of permutations of 1..n with sum (i-p(i))^2 < n*(n-1)/2.

Terms

    a(0) =0a(1) =1a(2) =3a(3) =5a(4) =21a(5) =87a(6) =350a(7) =1399a(8) =6689a(9) =36711a(10) =196510a(11) =1037354a(12) =6147299a(13) =40106433a(14) =256572630a(15) =1621282565a(16) =11156001505a(17) =82732094377a(18) =603846490132

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