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A192285 Primitive pseudo anti-perfect numbers 0
5, 7, 8, 17, 22, 23, 31, 33, 38, 39, 41, 52, 53, 59, 67, 71, 73, 74, 81, 83, 94, 101, 103, 108, 109, 116, 122, 127, 129, 137, 143, 149, 151, 157, 158, 167, 171, 172, 178, 179, 193, 199, 214, 237, 241, 247, 257, 262, 263, 269, 283, 293, 311, 313, 319, 331, 333 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

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

Like A006036 but using anti-divisors.

Subset of A192270.

LINKS

Table of n, a(n) for n=1..57.

MAPLE

with(combinat);

P:=proc(i)

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

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

for n from 1 to i do

  a:={};

  for k from 2 to n-1 do

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

  od;

  S:=subsets(a);

  while not S[finished] do

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

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

       else

          ok:=1;

          for k from 1 to j do

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

          od;

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

       fi;

    fi;

  od;

od;

end:

CROSSREFS

Cf. A006036, A066272, A192270

Sequence in context: A140237 A032683 A182005 * A192123 A104423 A011347

Adjacent sequences:  A192282 A192283 A192284 * A192286 A192287 A192288

KEYWORD

nonn

AUTHOR

Paolo P. Lava, Jul 20 2011

STATUS

approved

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Last modified November 19 06:50 EST 2017. Contains 294915 sequences.