153400domain: NAppears in sequencesTriangular array counting derangements by number of descents.at n=38A219836Irregular triangle of denominators of the average value of the first letter over all derangements of {1, 2, ..., n} with k descents.at n=34A332010a(n) = floor( (4/5)*( (9/4)^(n+1)-1 ) ).at n=14A361506