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%I #5 Jun 09 2017 13:57:33
%S 1,2,2,4,8,32,184,15392,5400584,74651892640,25003708306137848,
%T 6335942056759761366725617280,
%U 20682199297864337408779128828731176793076928
%N Product of a(n-2) and digit reversal of a(n-1).
%C Cf. A000301 a(n) = a(n-1)*a(n-2), A004086 R(n) = digit reversal of n, A109214 a(n)=a(n-1)*R(a(n-2)).
%F a(n)=a(n-2)*R(a(n-1)).
%e a(5)=8, a(6)=32, R(32)=23, hence a(7)=8*23=184; R(184)=841, a(8)=32*841=15392, etc.
%t a[1]=1;a[2]=2;a[n_]:=a[n]=a[n-2]*FromDigits[Reverse[IntegerDigits[a[n-1]]]]; A109213=Table[a[n], {n, 13}]
%t nxt[{a_,b_}]:={b,a*IntegerReverse[b]}; NestList[nxt,{1,2},15][[All,1]] (* Requires Mathematica version 10 or later *) (* _Harvey P. Dale_, Jun 09 2017 *)
%Y Cf. A000301, A004086, A109214.
%K base,nonn
%O 1,2
%A _Zak Seidov_, Jun 22 2005
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