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%I #4 Jun 27 2020 11:42:28
%S 1,4,6,8,10,12,14,16,18,20,22,24,26,27,30,32,34,35,38,40,42,44,46,48,
%T 50,51,54,56,57,60,62,64,65,68,70,72,74,76,77,80,82,84,86,87,90,92,93,
%U 95,98,100,102
%N Nonprimes b with result 1 under iterations of {r mod (max prime p < r)} starting at r = b.
%C Subsequence of A175071. Union of a(n) and A175073 is A175071.
%C Union of a(n) and A175073 is A175071. [From _Jaroslav Krizek_, Jan 30 2010]
%e Iteration procedure for a(5) = 10: 10 mod 7 = 3, 3 mod 2 = 1.
%t np1Q[n_]:=!PrimeQ[n]&&MemberQ[NestWhileList[Mod[#,NextPrime[#,-1]]&,n,#>0&],1]; Select[Range[150],np1Q] (* _Harvey P. Dale_, Jun 27 2020 *)
%K nonn
%O 1,2
%A _Jaroslav Krizek_, Jan 23 2010