Number of permutations p of [n] such that four is the maximum of the number of elements in any integer interval [p(i)..i+n*[i<p(i)]].

A324631

Number of permutations p of [n] such that four is the maximum of the number of elements in any integer interval [p(i)..i+n*[i<p(i)]].

Terms

    a(0) =15a(1) =31a(2) =60a(3) =113a(4) =215a(5) =406a(6) =763a(7) =1431a(8) =2676a(9) =4993a(10) =9299a(11) =17290a(12) =32103a(13) =59535a(14) =110292a(15) =204137a(16) =377535a(17) =697742a(18) =1288763a(19) =2379167a(20) =4390148a(21) =8097681a(22) =14931075a(23) =27522586a(24) =50719103a(25) =93444207a(26) =172125100a(27) =316999057a(28) =583718215a(29) =1074702870

External references