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%I #4 Mar 30 2012 17:31:23
%S 1357323,1357324,1562041,1562042,1671903,1671904,1889953,1889954,
%T 2010855,2010856,3826141,3826142,3851581,3851582,3933721,3933722,
%U 4652475,4652476,4652501,4738773,4738774,5518809,5518810,5826123
%N Where A121561(n) = 4.
%H Robert G. Wilson v, <a href="/A138027/b138027.txt">Table of n, a(n) for n = 1..100148</a>.
%t LrgstPrm[n_] := Block[{k = n}, While[ !PrimeQ@k, k-- ]; k]; f[n_] := Block[{c = 0, d = n}, While[d > 1, d = d - LrgstPrm@ d; c++ ]; c]; lst = {}; Do[ If[f@n == 3, AppendTo[lst,n], {n, 10^4}]; lst
%Y Cf. A121561, A093515, A093513, A138026.
%K nonn
%O 1,1
%A _Robert G. Wilson v_, Feb 27 2008, Mar 06 2008