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Smallest k such that in the interval [1,k] in A242033 all odd primes <= prime(n) are present.
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%I #20 Apr 26 2021 06:33:11

%S 1,4,9,54,54,88,88,220,220,444,444,570,570,570,896,1510,1510,1510,

%T 1510,1695,2065,2249,2249,2968,2968,2968,2968,3341,4561,4561,4561,

%U 4942,4942,6471,6471,6471,7158,9202,9202,10915,10915,10915,10915,12312,12312,12312

%N Smallest k such that in the interval [1,k] in A242033 all odd primes <= prime(n) are present.

%t lpf[n_]:=lpf[n]=First[First[FactorInteger[n]]]; (* least prime factor *)

%t A242033=Map[lpf[#-1]&,Select[Range[6,100000,2],lpf[#-1]<lpf[#-3]&](*A245024*)];

%t pos={};NestWhile[#+1&,2,(AppendTo[pos,Position[A242033,Prime[#],1,1]];!Last[pos]=={})&];

%t A242036=Rest[FoldList[Max,-Infinity,Flatten[pos]]] (* _Peter J. C. Moses_, Aug 14 2014 *)

%Y Cf. A245024, A243937, A242033, A242034.

%K nonn

%O 2,2

%A _Vladimir Shevelev_, Aug 12 2014

%E More terms from _Peter J. C. Moses_, Aug 12 2014