A245428 - OEIS

%I #10 Jul 22 2014 12:35:31

%S 10,30,100,330,1100,3670,12230,40770,135900,453000,1510000,5033330,

%T 16777770,55925900,186419660,621398870,2071329570,6904431900,

%U 23014773000,76715910000,255719700000,852399000000,2841330000000,9471100000000,31570333333330,105234444444430

%N Number of nonnegative integers with property that their base 10/3 expansion (see A024658) has n digits.

%e a(2) = 30 because 30, 31,.., 60, 61, .., 98 and 99 are the base 10/3 expansions for the integers 10, 11, .., 20, 21,.., 38, and 39 respectively and these are the only integers with 2 digits.

%o (Sage)

%o A=[1]

%o for i in [1..60]:

%o     A.append(ceil(((10-3)/3)*sum(A)))

%o [10*x for x in A]

%Y Cf. A024658, A081848, A245356.

%K nonn,base

%O 1,1

%A _Hailey R. Olafson_, Jul 21 2014