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%I #22 Jan 19 2019 12:41:30
%S 1,1,1,37,43,439,31321,3555900001,3555900001,3563253697383401592719,
%T 3563253697383401592719,
%U 2069957682701324503311258278145695430463576158940397351,7609174114451381087553287043297264970128251910800933517241956209
%N a(1)=1, a(2)=1; for n > 2, a(n) is the largest noncomposite proper divisor of the concatenation of terms a(1) through a(n-1).
%t FromDigits /@ Nest[Append[#, IntegerDigits@ Select[Divisors[FromDigits[Join @@ #]], ! CompositeQ@ # &][[-1]] ] &, {{1}, {1}, {1}}, 7] (* _Michael De Vlieger_, Nov 26 2018 *)
%Y Cf. A322097.
%K nonn,base
%O 1,4
%A _John Mason_, Nov 26 2018
%E a(12) corrected and a(13) added by _Daniel Suteu_, Jan 19 2019
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