%I #11 Jun 13 2015 00:52:17
%S 10,100,994,9796,95650,924820,8845714,83575396,778945090,7156197940,
%T 64800104434,578648865796,5100362368930,44424892053460,
%U 382839350691154,3268062540952996,27665402010407170,232490197792427380,1941315874498269874
%N a(n) is the number of nonnegative integers k less than 10^n such that the decimal representation of k lacks at least one of the digits 1,2,3 and at least one of the digits 4,5,6,7,8,9.
%H Colin Barker, <a href="/A125897/b125897.txt">Table of n, a(n) for n = 1..1000</a>
%H Milan Janjic, <a href="http://www.pmfbl.org/janjic/">Enumerative Formulas for Some Functions on Finite Sets</a>
%H <a href="/index/Rec#order_08">Index entries for linear recurrences with constant coefficients</a>, signature (36,-546,4536,-22449,67284,-118124,109584,-40320).
%F a(n) = 18*8^n-63*7^n+111*6^n-120*5^n+83*4^n-36*3^n+9*2^n-1.
%F G.f.: -2*x*(20160*x^7 -54792*x^6 +53344*x^5 -28304*x^4 +8374*x^3 -1427*x^2 +130*x -5) / ((x -1)*(2*x -1)*(3*x -1)*(4*x -1)*(5*x -1)*(6*x -1)*(7*x -1)*(8*x -1)). - _Colin Barker_, Feb 23 2015
%p f:=n->18*8^n-63*7^n+111*6^n-120*5^n+83*4^n-36*3^n+9*2^n-1;
%o (PARI) vector(100, n, 18*8^n-63*7^n+111*6^n-120*5^n+83*4^n-36*3^n+9*2^n-1) \\ _Colin Barker_, Feb 23 2015
%Y Cf. A125630.
%K nonn,base,easy
%O 1,1
%A Aleksandar M. Janjic and _Milan Janjic_, Feb 03 2007
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