This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A072912 #9 Jun 08 2019 17:56:30 %S A072912 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 A072912 11,11,11,12,12,12,13,13,13,14,14,14,15,15,15,16,16,16,17,17,17,18,18, %U A072912 18,18,19,19,19,20,20,20,21,21,21,22,22,22,23,23,23,24,24,24,25,25,25 %N A072912 Number of Fibonacci numbers F(k) <= 10^n which end in 0. %F A072912 a(n) = ceiling(n*log(10)/(15*log(phi))) +0 or +1. %e A072912 a(2)=6 because there are 6 Fibonacci numbers F(k) <= 10^2 which end in 0. %o A072912 (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 A072912 Different from A002280. %Y A072912 Cf. A008597, A214855. %K A072912 base,nonn %O A072912 0,4 %A A072912 _Shyam Sunder Gupta_ and _Benoit Cloitre_, Aug 15 2002