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%I #5 Mar 29 2015 19:42:29
%S 1,1,2,3,5,8,1,3,9,4,12,1,3,16,1,3,4,1,9,1,7,4,7,5,10,10,8,1,1,1,1,12,
%T 1,5,20,18,9,2,2,2,1,3,1,3,6,2,5,38,2,7,1,1,4,4,3,4,4,4,9,8,7,4,3,40,
%U 9,8,2,5,8,7,7,8,8,1,3,1,7,1,5,1,1,7,4,3,4,9,1,7,10,7,1,3,1,5,14,1,5,16,9,4
%N "Fibonacci in digits - up and down": start with a(1)=1, a(2)=1; repeatedly adjoin either the sum of the two previous terms (if that sum happens to be even) or else adjoin digits of the sum of previous two terms (if that sum happens to be odd).
%e ... a(6)=a(4)+a(5), a(7)=left digit of (a(5)+a(6)=5+8=1 3) as 13 is odd, a(8)=right digit of (a(5)+a(6)=5+8=1 3) as 13 is odd, a(11)=a(8)+a(9) as even ...
%t a = {0, 1}; f[n_] := Block[{k = a[[n - 1]] + a[[n - 2]]}, If[ EvenQ[k], AppendTo[a, k], a = Join[a, IntegerDigits[k]] ]]; Do[ f[n], {n, 3, 100}]; a (* _Robert G. Wilson v_, Mar 27 2004 *)
%Y Cf. A093086, A093087, A093088, A093089, A093090, A093091.
%K nonn,base
%O 1,3
%A _Bodo Zinser_, Mar 20 2004
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