a(n) = ((2^b-1)/phi(n))*Sum_{d|n} Moebius(n/d)*d^(b-1) for b = 8.

Terms

a(0) =255a(1) =32385a(2) =278715a(3) =2072640a(4) =4980405a(5) =35396805a(6) =35000535a(7) =132648960a(8) =203183235a(9) =632511435a(10) =496922835a(11) =2265395520a(12) =1333405965a(13) =4445067945a(14) =5443582665a(15) =8489533440a(16) =6539772585a(17) =25804270845a(18) =12663182955a(19) =40480731840a(20) =38255584755a(21) =63109200045a(22) =39465022215a(23) =144985313280