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A166931
Numbers n with property that n mod k is k-1 for all k = 2..9.
1
2519, 5039, 7559, 10079, 12599, 15119, 17639, 20159, 22679, 25199, 27719, 30239, 32759, 35279, 37799, 40319, 42839, 45359, 47879, 50399, 52919, 55439, 57959, 60479, 62999, 65519, 68039, 70559, 73079, 75599, 78119, 80639, 83159, 85679
OFFSET
1,1
FORMULA
a(n) = 2519 + n*2520.
From G. C. Greubel, May 28 2016: (Start)
a(n) = 2*a(n-1) - a(n-2).
G.f.: (2519 + x)/(1-x)^2.
E.g.f.: (2519 + 2520*x)*exp(x). (End)
MAPLE
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
MATHEMATICA
Select[Range[90000], And@@Table[Mod[#, k]==k-1, {k, 2, 9}]&] (* Harvey P. Dale, Jun 14 2011 *)
LinearRecurrence[{2, -1}, {2519, 5039}, 50] (* G. C. Greubel, May 28 2016 *)
CROSSREFS
Sequence in context: A250694 A250679 A145534 * A131662 A068352 A175754
KEYWORD
nonn,easy
AUTHOR
Luc Comeau-Montasse, Oct 23 2009
EXTENSIONS
Edited by N. J. A. Sloane, Oct 25 2009
STATUS
approved