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A272576 a(n) = f(10, f(9, n)), where f(k,m) = floor(m*k/(k-1)).

%I A272576 #28 Nov 07 2022 20:26:35
%S A272576 0,1,2,3,4,5,6,7,10,11,12,13,14,15,16,17,20,21,22,23,24,25,26,27,30,
%T A272576 31,32,33,34,35,36,37,40,41,42,43,44,45,46,47,50,51,52,53,54,55,56,57,
%U A272576 60,61,62,63,64,65,66,67,70,71,72,73,74,75,76,77,80,81,82,83,84,85,86,87,90
%N A272576 a(n) = f(10, f(9, n)), where f(k,m) = floor(m*k/(k-1)).
%C A272576 Also, numbers not ending with the digit 8 or 9.
%C A272576 The initial terms coincide with those of A007094 and A039155. First disagreement is after 77 (index 63): a(64) = 80, A007094(64) = 100 and A039155(65) = 89.
%H A272576 <a href="/index/Rec#order_09">Index entries for linear recurrences with constant coefficients</a>, signature (1,0,0,0,0,0,0,1,-1).
%H A272576 <a href="/index/Ar#10-automatic">Index entries for 10-automatic sequences</a>.
%F A272576 G.f.: x*(1 + x + x^2 + x^3 + x^4 + x^5 + x^6 + 3*x^7)/((1 + x)*(1 - x)^2*(1 + x^2) *(1 + x^4)).
%F A272576 a(n) = a(n-1) + a(n-8) - a(n-9).
%F A272576 a(n) = 1.25n + O(1). - _Charles R Greathouse IV_, Nov 07 2022
%p A272576 f := (k, m) -> floor(m*k/(k-1)):
%p A272576 a := n -> f(10, f(9,n)):
%p A272576 seq(a(n), n = 0..72); # _Peter Luschny_, May 03 2016
%t A272576 f[k_, m_] := Floor[m*k/(k-1)];
%t A272576 a[n_] := f[10, f[9, n]];
%t A272576 Table[a[n], {n, 0, 72}] (* _Jean-François Alcover_, May 09 2016 *)
%t A272576 LinearRecurrence[{1,0,0,0,0,0,0,1,-1},{0,1,2,3,4,5,6,7,10},90] (* _Harvey P. Dale_, Jun 22 2017 *)
%o A272576 (Magma) k:=10; f:=func<k,m | Floor(m*k/(k-1))>; [f(k,f(k-1,n)): n in [0..70]];
%o A272576 (Sage)
%o A272576 f = lambda k, m: floor(m*k/(k-1))
%o A272576 a = lambda n: f(10, f(9, n))
%o A272576 [a(n) for n in range(73)] # _Peter Luschny_, May 03 2016
%o A272576 (PARI) is(n)=n%10<8 \\ _Charles R Greathouse IV_, Feb 13 2017
%Y A272576 Cf. similar sequences listed in A272574.
%K A272576 nonn,easy,base
%O A272576 0,3
%A A272576 _Bruno Berselli_, May 03 2016