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Rearrangement of positive integers except 3 defined by A083758.
3

%I #12 Oct 21 2020 12:52:19

%S 1,2,5,4,13,11,7,38,9,22,45,53,10,12,17,44,49,50,52,85,158,68,55,229,

%T 97,8,62,269,256,159,41,73,54,179,581,210,98,297,86,34,43,273,199,122,

%U 16,153,140,29,709,521,64,163,87,389,1145,106,164,231,26,177,28,464,51,258,398,391

%N Rearrangement of positive integers except 3 defined by A083758.

%C This is conjectured to be a permutation of all positive integers except 3.

%C Apply PrimePi (A000720) to the terms of A083758.

%o (PARI) a338073(m)={my(np=1000*m,pused=vectorsmall(np),digp=[]);for(n=1,m,my(found=0);for(k=1,np, if(!pused[k],my(add=digits(prime(k)),pc=concat(digp,add));if(ispseudoprime(fromdigits(pc)),print1(k,", ");digp=pc;pused[k]=1;found=1;break)));if(!found,break))};

%o a338073(66) \\ _Hugo Pfoertner_, Oct 21 2020

%Y Cf. A000720, A083758, A083759, A338072.

%K nonn

%O 1,2

%A _N. J. A. Sloane_, Oct 20 2020