A109941 - OEIS

%I #9 Dec 05 2013 19:57:01

%S 45,2430,165150,12370500,989955000,82499850000,7071428928571,

%T 618749955000000,55000000350000000,4949999995500000000,

%U 449999999955000000000,41250000000150000000000,3807692307689192307692307,353571428571466428571428572,32999999999999850000000000000

%N Sum of all n-digit multiples of n.

%e a(2) = 2430, a(2) = 10 +12+...+96+98 = 45*(10+98)/2.

%t Table[Sum[i, {i, n*Ceiling[(10^(n - 1))/n], 10^n - 1, n}], {n, 15}] (* Hans Havermann *)

%K base,nonn

%O 1,1

%A _Amarnath Murthy_, Jul 19 2005

%E More terms from _Hans Havermann_, Jul 22 2005