%I #12 Sep 08 2022 08:45:55
%S 1,0,15,0,25,12,35,0,45,0,11,0,65,0,75,32,85,0,95,0,21,0,115,0,125,52,
%T 135,0,145,0,31,0,165,0,175,72,185,0,195,0,41,0,215,0,225,92,235,0,
%U 245,0,51,0,265,0,275,112,285,0,295,0,61,0,315,0,325,132,335,0,345,0,71,0
%N Smallest number that equals n times its last digit, or 0 if no such number exists.
%e a(7) = 35 because last digit of 35 is 5 and 7*5 = 35, and there is no number < 35 that satisfies the condition.
%p with(numtheory):for k from 1 to 100 do:id:=0:for n from 1 to 2000 while(id=0)
%p do:x:=irem(n,10):if n=k*x then n0:=n:id:=1:else fi:od:if id=1 then printf(`%d,
%p `,n0):else printf(`%d, `,0):fi:od:
%o (Magma) A186436:=function(n); for j in [1..9] do a:=n*j; if j eq Intseq(a)[1] then return a; end if; end for; return 0; end function; [ A186436(n): n in [1..100] ]; // _Klaus Brockhaus_, Feb 22 2011
%K nonn,easy,base
%O 1,3
%A _Michel Lagneau_, Feb 21 2011
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