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A111667
Abundance of admirable numbers.
3
4, 2, 12, 12, 10, 12, 12, 8, 12, 4, 12, 56, 4, 12, 2, 12, 120, 12, 56, 12, 12, 12, 56, 78, 12, 12, 180, 12, 56, 12, 12, 56, 12, 8, 12, 12, 12, 2, 12, 56, 12, 56, 12, 12, 12, 12, 12, 56, 2, 12, 672, 12, 12, 12, 56, 12, 12, 8, 56, 12, 12, 12, 30, 12, 32, 12, 56, 12, 12, 12, 12, 56
OFFSET
1,1
LINKS
EXAMPLE
a(1)=4 because the first admirable number is 12 and sigma(12)-24 = 4.
MATHEMATICA
fn[n_]:=DivisorSigma[1, n]-2*n; fn/@Select[Range[1155], MemberQ[Most[Divisors[#]], (DivisorSigma[1, #]-2*#)/2]&] (* James C. McMahon, Jun 02 2024 *)
CROSSREFS
Sequence in context: A167591 A227043 A143376 * A323825 A019239 A143944
KEYWORD
easy,nonn
AUTHOR
Jason Earls, Aug 14 2005
STATUS
approved