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Number of nonnegative integers with property that their base 8/7 expansion (see A024649) has n digits.
0

%I #14 Jul 22 2014 20:11:36

%S 8,8,8,8,8,8,8,8,16,16,16,16,24,24,32,32,40,40,48,56,64,72,80,96,112,

%T 128,144,160,184,216,240,280,320,360,416,472,544,616,704,808,920,1056,

%U 1208,1376,1576,1800,2056,2352,2688,3072,3512,4008,4584

%N Number of nonnegative integers with property that their base 8/7 expansion (see A024649) has n digits.

%C The numbers 8-15 are represented by 70, 71, 72, 73, 74, 75, 76, 77 respectively in base 8/7. These are the only integers with two digits, and so a(2)=8.

%F a(n) = 8*A120186(n).

%o (Sage)

%o A=[1]

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

%o A.append(ceil((8-7)/7*sum(A)))

%o [8*x for x in A]

%Y Cf. A081848, A024649, A120186.

%K nonn,base

%O 1,1

%A _James Van Alstine_, Jul 21 2014