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%I #10 Sep 08 2022 08:45:57
%S 2,3,23,347,349,311,391627,3471331,384067,2310175897,239111323273399,
%T 23167,3784097136227,235983149249,3428116271,37111677121283,23293,
%U 3471949133311,231314228398154359,378112153101159371,2379127163381
%N The primes created by concatenation of anti-divisors in A191647.
%C a(n) is the concatenation of the anti-divisors of A191647(n).
%H Klaus Brockhaus, <a href="/A191859/b191859.txt">Table of n, a(n) for n = 1..1000</a>
%e A191647(6) = 16, the anti-divisors of 16 are 3, 11. Hence a(6) = 311.
%e A191647(8) = 46, the anti-divisors of 46 are 3, 4, 7, 13, 31. Hence a(8) = 3471331.
%o (Magma) Antidivisors:=func< n | [ d: d in [2..n-1] | n mod d ne 0 and ( (IsEven(d) and 2*n mod d eq 0) or (IsOdd(d) and ((2*n-1) mod d eq 0 or (2*n+1) mod d eq 0)) ) ] >; CAD:=function(n); A:=Antidivisors(n); S:=[]; for k in [1..#A] do S:= Intseq(A[k]) cat S; end for; p:=Seqint(S); return p; end function; A191859List:=func< m | [ p: n in [1..m] | IsPrime(p) where p is CAD(n) ] >; A191859List(600);
%Y Cf. A191647, A066272, A130846, A120712.
%K nonn,base
%O 1,1
%A _Klaus Brockhaus_, Jun 18 2011