

A272576


a(n) = f(10, f(9, n)), where f(k,m) = floor(m*k/(k1)).


1



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, 31, 32, 33, 34, 35, 36, 37, 40, 41, 42, 43, 44, 45, 46, 47, 50, 51, 52, 53, 54, 55, 56, 57, 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
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OFFSET

0,3


COMMENTS

Also, numbers not ending with the digit 8 or 9.
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.


LINKS



FORMULA

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)).
a(n) = a(n1) + a(n8)  a(n9).


MAPLE

f := (k, m) > floor(m*k/(k1)):
a := n > f(10, f(9, n)):


MATHEMATICA

f[k_, m_] := Floor[m*k/(k1)];
a[n_] := f[10, f[9, n]];
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 *)


PROG

(Magma) k:=10; f:=func<k, m  Floor(m*k/(k1))>; [f(k, f(k1, n)): n in [0..70]];
(Sage)
f = lambda k, m: floor(m*k/(k1))
a = lambda n: f(10, f(9, n))


CROSSREFS

Cf. similar sequences listed in A272574.


KEYWORD

nonn,easy,base


AUTHOR



STATUS

approved



