A192285 - OEIS

%I #5 Mar 30 2012 18:53:49

%S 5,7,8,17,22,23,31,33,38,39,41,52,53,59,67,71,73,74,81,83,94,101,103,

%T 108,109,116,122,127,129,137,143,149,151,157,158,167,171,172,178,179,

%U 193,199,214,237,241,247,257,262,263,269,283,293,311,313,319,331,333

%N Primitive pseudo anti-perfect numbers

%C A primitive pseudo anti-perfect number is a pseudo anti-perfect number that is not a multiple of any other pseudo anti-perfect number.

%C Like A006036 but using anti-divisors.

%C Subset of A192270.

%p with(combinat);

%p P:=proc(i)

%p local a,j,k,n,ok,S,v;

%p v:=array(1..10000); j:=0;

%p for n from 1 to i do

%p   a:={};

%p   for k from 2 to n-1 do

%p     if abs((n mod k)- k/2) < 1 then a:=a union {k}; fi;

%p   od;

%p   S:=subsets(a);

%p   while not S[finished] do

%p     if convert(S[nextvalue](), `+`)=n then

%p        if j=0 then j:=1; v[1]:=n; print(n); break;

%p        else

%p           ok:=1;

%p           for k from 1 to j do

%p               if trunc(n/v[k])=n/v[k] then ok:=0; break; fi;

%p           od;

%p           j:=j+1; v[j]:=n; if ok=1 then print(n); fi;

%p        fi;

%p     fi;

%p   od;

%p od;

%p end:

%Y Cf. A006036, A066272, A192270

%K nonn

%O 1,1

%A _Paolo P. Lava_, Jul 20 2011