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Natural numbers m with result 1 under iterations of {r mod (max prime p < r)} starting at r = m.
6

%I #4 May 05 2015 18:42:42

%S 1,3,4,6,8,10,11,12,14,16,17,18,20,22,23,24,26,27,29,30,32,34,35,37,

%T 38,40,41,42,44,46,47,48,50,51,53,54,56,57,59,60,62,64,65,67,68,70,71,

%U 72,74,76,77,79,80,82,83,84,86,87,89,90,92,93,95,97,98,100,101,102

%N Natural numbers m with result 1 under iterations of {r mod (max prime p < r)} starting at r = m.

%C Complement of A175072. Union of A175073 and A175074. [From _Jaroslav Krizek_, Jan 30 2010]

%e Iteration procedure for a(6) = 10: 10 mod 7 = 3, 3 mod 2 = 1. Iteration procedure for a(7) = 11: 11 mod 7 = 4, 4 mod 3 = 1.

%t nn1Q[n_]:=Last[NestWhileList[Mod[#,NextPrime[#,-1]]&,n,#>1&]]!=0; Select[ Range[ 110],nn1Q] (* _Harvey P. Dale_, May 05 2015 *)

%K nonn

%O 1,2

%A _Jaroslav Krizek_, Jan 23 2010