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%I #17 Dec 04 2020 10:46:48
%S 12,36,56,108,234,260,324,351,456,476,570,624,780,855,880,972,992,
%T 1428,1508,1550,2325,2340,2442,2516,2870,2916,3116,3354,3663,3875,
%U 4284,4305,4524,5031,5328,6136,6710,6954,7020,7076,7175,7548,7584,7952,8748,9230,9348,9480,10065,10074,10176,10431
%N Numbers k such that A001222(k)>=3 and A339423(k) divides k.
%C Terms of A339424 that are not semiprimes.
%C The only term in A014612 is 12.
%C The terms in A014613 are 36 and p*q*r*s where p<=q<=r<=s are primes and s=1+q+q*r.
%H Robert Israel, <a href="/A339425/b339425.txt">Table of n, a(n) for n = 1..1000</a>
%e a(5) = 234 = 2*3*3*13 is a term because A339423(234)=2+2*3+2*3*3=26 divides 234.
%p R:= NULL: count:= 0:
%p for n from 4 while count < 100 do
%p if isprime(n) then next fi;
%p F:= sort(map(t -> t[1]$t[2], ifactors(n)[2]));
%p if nops(F)=2 then next fi;
%p T:= 0; P:= 1;
%p for j from 1 to nops(F)-1 do
%p P:= P*F[j];
%p T:= T+P;
%p od;
%p if n mod T = 0 then
%p R:= R, n; count:= count+1
%p fi
%p od:
%p R;
%o (PARI) conv(n) = {my(f=factor(n), v=vector(bigomega(n)), k=1); for (i=1, #f~, for (j=1, f[i,2], v[k] = f[i,1]; k++;);); v;}
%o f(n) = {my(v=conv(n)); sum(k=1, #v-1, prod(j=1, k, v[j]));} \\ A339423
%o isok(k) = (bigomega(k) >= 3) && ((k % f(k)) == 0); \\ _Michel Marcus_, Dec 04 2020
%Y Cf. A001222, A001358, A014612, A014613, A339423, A339424.
%K nonn
%O 1,1
%A _J. M. Bergot_ and _Robert Israel_, Dec 03 2020
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