Number of discordant permutations.

Terms

a(0) =20a(1) =371a(2) =2588a(3) =11097a(4) =35645a(5) =94457a(6) =218124a(7) =454220a(8) =872648a(9) =1571715a(10) =2684936a(11) =4388567a(12) =6909867a(13) =10536089a(14) =15624200a(15) =22611330a(16) =32025950a(17) =44499779a(18) =60780420a(19) =81744725a(20) =108412889a(21) =141963273a(22) =183747956a(23) =235309016a(24) =298395540