%I A089908
%S A089908 0,28,609,9555,130501,1654947,20049393,235493839,2704938285,30549382731,
%T A089908 340493827177,3754938271623,41049382716069,445493827160515,
%U A089908 4804938271604961,51549382716049407,550493827160493853
%N A089908 Sum of digits of numbers between 0 and (7/9)*(10^n-1).
%C A089908 From a suggestion of Yalcin Aktar (aktaryalcin(AT)msn.com)
%F A089908 a(n)=s(7, n-1) where s(a, k)=a*(k+1)+a^2*sum(i=0, k, i*10^(k-i))+sum(i=0, 
               k, 5*a*(9*(k-i)+a- 1)*10^(k-i-1))
%Y A089908 Cf. A089903, A089904, A089905, A087330, A089906, A089907, A089909, A034967.
%Y A089908 Sequence in context: A107397 A053110 A004371 this_sequence A038121 A070310 
               A160141
%Y A089908 Adjacent sequences: A089905 A089906 A089907 this_sequence A089909 A089910 
               A089911
%K A089908 nonn,base
%O A089908 0,2
%A A089908 Benoit Cloitre (benoit7848c(AT)orange.fr), Nov 14 2003