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A192271
Anti-weird numbers.
0
11, 12, 13, 14, 15, 18, 20, 21, 25, 27, 28, 30, 37, 40, 42, 43, 46, 47, 48, 50, 55, 57, 58, 62, 65, 66, 75, 78, 80, 84, 86, 87, 90, 91, 92, 93, 97, 99, 100, 107, 111, 113, 118, 119, 120, 121, 124, 125, 126, 128, 132, 133, 135, 136, 140, 142, 145, 152, 153, 155, 160, 161, 163, 168, 170, 173, 177, 180, 181, 183, 184, 186, 188, 190, 192, 196, 197, 198, 204, 205, 208, 210, 212, 213, 218, 222, 223
OFFSET
1,1
COMMENTS
Like A006037 but using anti-divisors: Anti-weird numbers are anti-abundant (A192268) but not pseudo anti-perfect (A192270).
EXAMPLE
25 is an anti-weird number because it is anti-abundant (its anti-divisors are 2, 3, 7, 10, 17 and their sum is 39 > 25) and no subsets of its anti-divisors add up to 25.
MAPLE
# see A066272
isA192270 := proc(n) local a, S ; a := antidivisors(n) ; S := combinat[subsets](a) ; while not S[finished] do if convert(S[nextvalue](), `+`) = n then return true; end if; end do; false ; end proc:
isA192268 := proc(n) A066417(n) > n ; end proc:
isA192271 := proc(n) isA192268(n) and not isA192270(n) ; end proc:
for n from 1 to 40 do if isA192271(n) then printf("%d, ", n) ; end if; end do: # R. J. Mathar, Jul 04 2011
CROSSREFS
KEYWORD
nonn
AUTHOR
Paolo P. Lava, Jun 28 2011
STATUS
approved