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A109138 Numbers n such that 2^n + 2 is an admirable number (A111592). 0
6, 8, 12, 14, 18, 20, 24, 32, 44, 62, 80, 102, 128, 168, 192, 200, 314, 348, 702 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
For k > 1, A000978(k)+1 is a member. Are there any others? - David Wasserman, May 28 2008
No more terms below 1064. - Amiram Eldar, Oct 12 2019
LINKS
EXAMPLE
a(3)=12 because 2^12 + 2 = 4098 and 1+2+3+683+1366+2049-6 = 4098.
MATHEMATICA
fQ[n_] := Block[{d = Most[ Divisors[n]], k = 1}, l = Length[d]; s = Plus @@ d; While[k < l && s - 2d[[k]] > n, k++ ]; If[k > l || s != n + 2d[[k]], False, True]]; Do[ If[ fQ[2^n + 2], Print[n]], {n, 200}] (* Robert G. Wilson v, Aug 30 2005 *)
CROSSREFS
Cf. A000978.
Sequence in context: A242058 A322293 A366442 * A315858 A123303 A063207
KEYWORD
nonn,more
AUTHOR
Jason Earls, Aug 18 2005
EXTENSIONS
More terms from David Wasserman, May 28 2008
a(19) from Amiram Eldar, Oct 12 2019
STATUS
approved

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Last modified April 14 11:07 EDT 2024. Contains 371657 sequences. (Running on oeis4.)