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A086942
Integers k such that R(k+8) = 4.
2
32, 392, 3992, 39992, 399992, 3999992, 39999992, 399999992, 3999999992, 39999999992, 399999999992, 3999999999992, 39999999999992, 399999999999992, 3999999999999992, 39999999999999992, 399999999999999992, 3999999999999999992, 39999999999999999992
OFFSET
1,1
COMMENTS
R(a(n)) = A086943(n).
FORMULA
a(n) = 4*10^n-8.
G.f.: 8*x*(5*x+4)/((10*x-1)*(x-1)).
a(n) = 8 * A198971(n-1).
MATHEMATICA
4*10^Range[20] - 8 (* Paolo Xausa, Sep 21 2024 *)
PROG
(Magma) [4*10^n-8: n in [1..25]]; // Vincenzo Librandi, Aug 22 2011
CROSSREFS
KEYWORD
nonn,base,easy
AUTHOR
Ray Chandler, Jul 24 2003
STATUS
approved