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 A105506 #6 Oct 07 2016 12:06:56 %S A105506 15,20,39,63,82,87,106,130,149,154,173,197,216,221,240,259,264,283, %T A105506 288,307,326,331,350,355,374,393,398,417,422,441,460,465,484,508,527, %U A105506 532,551,575,594,599,618,642,661,666,685,709,728,733,752,771,776,795,800 %N A105506 Numbers m such that 6 is the leading digit of the n-th Fibonacci number in decimal representation. %C A105506 A008963(a(n)) = 6; A105516(a(n)) = A105516(a(n) - 1) + 1. %F A105506 a(n) ~ kn by the equidistribution theorem, where k = log(10)/(log(7) - log(6)) = 14.9372.... - _Charles R Greathouse IV_, Oct 07 2016 %e A105506 a(10)=154: A008963(154) = A000030(A000045(154)) = %e A105506 A000030(68330027629092351019822533679447) = 6. %o A105506 (PARI) is(n)=digits(fibonacci(n))[1]==6 \\ _Charles R Greathouse IV_, Oct 07 2016 %Y A105506 Cf. A000030, A000045, A072708, A105501, A105502, A105503, A105504, A105505, A105507, A105508, A105509. %K A105506 nonn,base %O A105506 1,1 %A A105506 _Reinhard Zumkeller_, Apr 11 2005