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%I #18 Jan 27 2014 09:25:59
%S 2,3,6,7,10,15,19,27,30,31,34,42,51,54,66,70,75,82,87,90,91,99,106,
%T 114,135,147,159,174,175,187,190,195,210,211,222,231,234,246,255,262,
%U 271,274,279,282,294,307,310,327,330,331,339,351,355,379,387,394,399,411,414
%N Numbers n such that A051732(n) = n-1.
%H Olivier Gérard and Vincenzo Librandi, <a href="/A051733/b051733.txt">Table of n, a(n) for n = 1..6000</a> (first 386 terms from Olivier Gérard).
%t (* v8 *) Select[Range[2,4000],Function[n,Sort[First[First[PermutationCycles@Join[Table[2r-1,{r,1,n}],Table[2r-2n,{r,n+1,2n}]]]]]==Range[2,2n-1]]] (* _Olivier Gérard_, Nov 08 2012 *)
%Y Cf. A051732. Equals A217948(n)/2.
%K easy,nonn
%O 1,1
%A Marie-Christine Haton (Marie-Christine.Haton(AT)loria.fr)