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A166931 Numbers n with property that n mod k is k-1 for all k = 2..9.

%I A166931 #18 Jan 28 2018 12:52:15
%S A166931 2519,5039,7559,10079,12599,15119,17639,20159,22679,25199,27719,30239,
%T A166931 32759,35279,37799,40319,42839,45359,47879,50399,52919,55439,57959,
%U A166931 60479,62999,65519,68039,70559,73079,75599,78119,80639,83159,85679
%N A166931 Numbers n with property that n mod k is k-1 for all k = 2..9.
%H A166931 G. C. Greubel, <a href="/A166931/b166931.txt">Table of n, a(n) for n = 1..1000</a>
%H A166931 <a href="/index/Rec#order_02">Index entries for linear recurrences with constant coefficients</a>, signature (2, -1).
%F A166931 a(n) = 2519 + n*2520.
%F A166931 From _G. C. Greubel_, May 28 2016: (Start)
%F A166931 a(n) = 2*a(n-1) - a(n-2).
%F A166931 G.f.: (2519 + x)/(1-x)^2.
%F A166931 E.g.f.: (2519 + 2520*x)*exp(x). (End)
%p A166931 isA166931 := proc(n) for k from 2 to 9 do if n mod k <> k-1 then return false; end if; end do; true; end proc: for n from 1 to 500000 do if isA166931(n) then printf("%d,",n) ; end if; end do ; # _R. J. Mathar_, Nov 02 2009
%t A166931 Select[Range[90000],And@@Table[Mod[#,k]==k-1,{k,2,9}]&] (* _Harvey P. Dale_, Jun 14 2011 *)
%t A166931 LinearRecurrence[{2, -1}, {2519, 5039}, 50] (* _G. C. Greubel_, May 28 2016 *)
%K A166931 nonn,easy
%O A166931 1,1
%A A166931 _Luc Comeau-Montasse_, Oct 23 2009
%E A166931 Edited by _N. J. A. Sloane_, Oct 25 2009