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A125732
Numbers n such that n=k*MiDi(n) for some integer k, where MiDi(n) = A103977(n) = "Minimal Difference of Divisors".
3
1, 2, 4, 8, 10, 16, 18, 32, 36, 44, 64, 72, 100, 128, 136, 144, 152, 162, 184, 196, 200, 256, 288, 324, 392, 400, 450, 512, 576, 648, 738, 748, 752, 784, 800, 882, 884, 900, 968, 1024, 1152, 1296, 1352, 1458, 1568, 1600, 1764, 1800, 1936, 2048, 2144, 2178, 2272
OFFSET
1,2
COMMENTS
A000079 is a subsequence because for n equal to a power of 2 the definition is satisfied by choosing k=n.
LINKS
MATHEMATICA
midi[n_] := Module[{d = Divisors[n], c, p, m}, c = CoefficientList[Product[1 + x^i, {i, d}], x]; p = -1 + Position[c, _?(# > 0 &)] // Flatten; m = Length[p]; If[OddQ[m], If[(d = p[[(m + 1)/2]] - p[[(m - 1)/2]]) == 1, 0, d], p[[m/2 + 1]] - p[[m/2]]]]; s = {}; Do[m = midi[n]; If[m > 0 && Divisible[n, m], AppendTo[s, n]], {n, 1, 2000}]; s (* Amiram Eldar, Dec 11 2019 *)
CROSSREFS
Sequence in context: A268497 A093886 A352203 * A032533 A062884 A026169
KEYWORD
nonn
AUTHOR
Yasutoshi Kohmoto, Jan 01 2007
EXTENSIONS
More terms from R. J. Mathar, Nov 27 2007
More terms from Amiram Eldar, Dec 11 2019
STATUS
approved