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%I #9 Jun 08 2019 17:56:30
%S 1,1,1,2,2,2,3,3,3,3,4,4,4,5,5,5,6,6,6,7,7,7,8,8,8,9,9,9,10,10,10,11,
%T 11,11,11,12,12,12,13,13,13,14,14,14,15,15,15,16,16,16,17,17,17,18,18,
%U 18,18,19,19,19,20,20,20,21,21,21,22,22,22,23,23,23,24,24,24,25,25,25
%N Number of Fibonacci numbers F(k) <= 10^n which end in 0.
%F a(n) = ceiling(n*log(10)/(15*log(phi))) +0 or +1.
%e a(2)=6 because there are 6 Fibonacci numbers F(k) <= 10^2 which end in 0.
%o (PARI) a(n) = (sum(i=0,ceil(n*log(10)/log((1+sqrt(5))/2)),if(fibonacci(i)%10+1+sign(fibonacci(i)-10^n),0,1)))
%Y Different from A002280.
%Y Cf. A008597, A214855.
%K base,nonn
%O 0,4
%A _Shyam Sunder Gupta_ and _Benoit Cloitre_, Aug 15 2002
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