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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: A243937 A242058 A322293 * A315858 A123303 A063207 Adjacent sequences:  A109135 A109136 A109137 * A109139 A109140 A109141 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 February 25 12:01 EST 2020. Contains 332233 sequences. (Running on oeis4.)