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A272141 Numbers such that the concatenation of their aliquot parts, in ascending order, are prime numbers.

%I A272141 #8 Apr 22 2016 23:48:38
%S A272141 9,14,21,26,27,34,35,46,49,55,57,58,62,74,98,115,118,143,155,158,161,
%T A272141 166,169,178,183,187,194,201,202,209,214,215,218,219,221,226,245,265,
%U A272141 279,287,295,298,309,314,323,326,327,329,335,341,355,371,374,377,381
%N A272141 Numbers such that the concatenation of their aliquot parts, in ascending order, are prime numbers.
%H A272141 Paolo P. Lava, <a href="/A272141/b272141.txt">Table of n, a(n) for n = 1..10000</a>
%e A272141 Aliquot parts of 9 are 1, 3 and concat(1,3) = 13 is prime;
%e A272141 aliquot parts of 3127 are 1, 53, 59 and concat(1,53,59) = 15359 is prime.
%p A272141 with(numtheory): P:= proc(q) local a,b,k,n;
%p A272141 for n from 1 to q do a:=sort([op(divisors(n))]); b:=0;
%p A272141 for k from 1 to nops(a)-1 do b:=b*10^(ilog10(a[k])+1)+a[k]; od;
%p A272141 if isprime(b) then print(n); fi; od; end: P(10^9);
%t A272141 Select[Range@ 384, PrimeQ@ FromDigits@ Flatten@ IntegerDigits@ Most@ Divisors@ # &] (* _Michael De Vlieger_, Apr 21 2016 *)
%Y A272141 Cf. A176553, A272142.
%K A272141 nonn,base,easy
%O A272141 1,1
%A A272141 _Paolo P. Lava_, Apr 21 2016