Number of permutations sigma of [n] such that (sigma(k) mod sigma(k+1)) <= (sigma(k+1) mod sigma(k+2)) for 1 <= k <= n - 2.

A332800

Number of permutations sigma of [n] such that (sigma(k) mod sigma(k+1)) <= (sigma(k+1) mod sigma(k+2)) for 1 <= k <= n - 2.

Terms

    a(0) =1a(1) =1a(2) =2a(3) =4a(4) =9a(5) =21a(6) =44a(7) =109a(8) =241a(9) =530a(10) =1176a(11) =3180a(12) =6456a(13) =14835a(14) =34672a(15) =81877a(16) =179434a(17) =479275a(18) =977224a(19) =2503363a(20) =5339049a(21) =11207391a(22) =28379591a(23) =82473713a(24) =166689486a(25) =370775384a(26) =877910547a(27) =2150475950a(28) =4608590865a(29) =12146671367

External references