A070869 - OEIS

%I #4 Mar 30 2012 17:30:43

%S 16,17,34,51,102,153,306,459,882,1197,2646,4347,11484,15273,24864,

%T 25443,50886,76329,152274,229371,458742,688113,1277910,2162607,

%U 6193008,6684333,12631680,12729219,25434054,38529033,76302162,115562715

%N a(1) = 16; a(n+1) = sum of a(n) and (a(n) written in base 2 and reversed).

%D S. Wolfram, A New Kind of Science, Wolfram Media, 2002; p. 125.

%e To get a(2) note that 16 = 10000 in base 2, reversing gives 00001, or 1 and so a(2) = 16 + 1 = 17.

%t a[1] = 16; a[n_] := Block[{b = IntegerDigits[ a[n - 1], 2]}, FromDigits[ b + Reverse[b], 2]]; Table[ a[n], {n, 1, 35}]

%K nonn,easy,base

%O 1,1

%A _N. J. A. Sloane_, May 19 2002

%E More terms from _Robert G. Wilson v_, May 20 2002