cp's OEIS Frontend

A036106 A summarize Fibonacci sequence: summarize the previous two terms!.

%I A036106 #12 Nov 02 2016 03:33:46
%S A036106 1,2,1211,2231,133241,14333231,24632241,1634534231,261544434231,
%T A036106 262564533241,363564435231,464544634221,463574533221,17363574434221,
%U A036106 37263554634231,37363554734231,37364544933221,1937263554933221
%N A036106 A summarize Fibonacci sequence: summarize the previous two terms!.
%C A036106 From the 26th term the sequence gets into a cycle of 46.
%H A036106 Reinhard Zumkeller, <a href="/A036106/b036106.txt">Table of n, a(n) for n = 0..254</a> = 5 periods.
%H A036106 <a href="/index/Sa#swys">Index to sequences related to say what you see</a>
%e A036106 a(24) = 293847463554538221;
%e A036106 a(25) = 294827365564537221 = first term of first period;
%e A036106 a(26) = 293837366554537221;
%e A036106 a(70) = 294837364554538221 = last term of first period != a(24);
%e A036106 a(71) = 294827365564537221 = a(25) = first term of second period;
%e A036106 a(72) = 293837366554537221 = a(26);
%e A036106 a(116) = 294837364554538221 = a(70) = last term of second period;
%e A036106 a(117) = 294827365564537221 = a(71) = first term of third period.
%t A036106 a[0] = 1; a[1] = 2; a[n_] := a[n] = Reverse /@ (IntegerDigits /@ {a[n-2], a[n-1]} // Flatten // Tally // Sort // Reverse) // Flatten // FromDigits; Table[a[n], {n, 0, 17}] (* _Jean-François Alcover_, Nov 02 2016 *)
%o A036106 (Haskell)
%o A036106 import Data.List (sort, group); import Data.Function (on)
%o A036106 a036106 n = a036106_list !! n
%o A036106 a036106_list = 1 : 2 : map (read . concatMap say . reverse . group . sort)
%o A036106                (zipWith ((++) `on` show) a036106_list $ tail a036106_list)
%o A036106                where say ws = (show $ length ws) ++ [head ws]
%o A036106 -- _Reinhard Zumkeller_, Oct 05 2015
%Y A036106 Cf. A036059.
%K A036106 base,easy,nice,nonn
%O A036106 0,2
%A A036106 _Floor van Lamoen_