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A061829 Multiples of 5 having only odd digits. 5

%I

%S 5,15,35,55,75,95,115,135,155,175,195,315,335,355,375,395,515,535,555,

%T 575,595,715,735,755,775,795,915,935,955,975,995,1115,1135,1155,1175,

%U 1195,1315,1335,1355,1375,1395,1515,1535,1555,1575,1595,1715,1735,1755

%N Multiples of 5 having only odd digits.

%H Robert Israel, <a href="/A061829/b061829.txt">Table of n, a(n) for n = 1..10000</a>

%H <a href="/index/Ar#10-automatic">Index entries for 10-automatic sequences</a>.

%F From _Robert Israel_, Jun 10 2018: (Start)

%F For n > 1, a(n) = 10*A014261(n-1) + 5.

%F a(5*n) = 25 + 10*a(n).

%F a(5*n+1) = 45 + 10*a(n).

%F a(5*n+2) = -35 + 10*a(n+1).

%F a(5*n+3) = -15 + 10*a(n+1).

%F a(5*n+4) = 5 + 10*a(n+1).

%F G.f. g(x) satisfies g(x) = -25 - 40*x + 5*(5+9*x-7*x^2-3*x^3+x^4)/(1-x^5) + 10*(1-x^5)*g(x^5)/(x^3*(1-x)).

%F (End)

%e 135 = 5*27 is a term having all odd digits.

%p L[1]:= [5]:

%p for n from 2 to 4 do

%p L[n]:= [seq(op(map(`+`,L[n-1],i*10^(n-1))),i=1..9,2)]

%p od:

%p map(op, [seq(L[i],i=1..4)]); # _Robert Israel_, Jun 10 2018

%t Select[5 Range[370],Select[IntegerDigits[#],EvenQ]=={}&] (* _Harvey P. Dale_, Feb 07 2011 *)

%o (PARI) is(n)=n%10==5 && #setintersect(Set(digits(n)),[0,2,4,6,8])==0 \\ _Charles R Greathouse IV_, Feb 15 2017

%Y Cf. A014261.

%K nonn,base,easy

%O 1,1

%A _Amarnath Murthy_, May 29 2001

%E More terms from Larry Reeves (larryr(AT)acm.org), May 30 2001

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Last modified July 29 13:28 EDT 2021. Contains 346346 sequences. (Running on oeis4.)