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%I #7 Jan 02 2019 13:12:58
%S 1,2,6,42,1770,3132915,9815156397249,96337295102457969494768070,
%T 9280874427658072275134580545332124401295103091525032,
%U 86134630141957550628261532252390058231417831318795074704890644033088478051503964693639295413423482601219
%N a(n) = a(n-1)^2 + Sum of the digits of a(n-1), with a(1)=1.
%H A. Frank & P. Jacqueroux, <a href="https://paulcooijmans.com/others/intcontest.pdf">International Contest</a>, 2001. Item 28
%e a(5) = 42^2 + (4 + 2) = 1770
%t NestList[#^2+Total[IntegerDigits[#]]&,1,10] (* _Harvey P. Dale_, Nov 30 2011 *)
%o (PARI) a=1; for(n=1,11,print1(a,",");sda=eval(Vec(Str(a)));a=a^2+sum(i=1,length(sda),sda[i]))
%K nonn,base
%O 1,2
%A Herman Jamke (hermanjamke(AT)fastmail.fm), Sep 30 2006
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