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 A280690 #9 Jan 12 2017 07:18:31 %S A280690 1,1,2,3,5,4,13,7,17,11,89,18,233,29,122,47,1597,76,4181,123,842,199, %T A280690 28657,322,15005,521,5777,843,514229,1364,1346269,2207,39602,3571, %U A280690 709805,5778,24157817,9349,271442,15127,165580141,24476,433494437,39603,1860497,64079,2971215073,103682,598364773,167761,12752042,271443 %N A280690 a(n) = A000045(n) / A105800(n); the n-th Fibonacci number divided by its largest Fibonacci proper divisor. %C A280690 A000045 is a divisibility sequence. %H A280690 Antti Karttunen, <a href="/A280690/b280690.txt">Table of n, a(n) for n = 1..377</a> %H A280690 Wikipedia, <a href="https://en.wikipedia.org/wiki/Divisibility_sequence">Divisibility sequence</a> %F A280690 a(n) = A000045(n) / A105800(n) = A000045(n) / A000045(A032742(n)). %F A280690 a(n) = A280687(A000045(n)). %F A280690 Other identities. For all n >= 1: %F A280690 a(A032742(n)) = A280689(n). %o A280690 (Scheme, two alternatives) %o A280690 (define (A280690 n) (/ (A000045 n) (A105800 n))) %o A280690 (define (A280690 n) (A280687 (A000045 n))) %Y A280690 Cf. A000045, A032742, A105800, A280687, A280689. %K A280690 nonn %O A280690 1,3 %A A280690 _Antti Karttunen_, Jan 11 2017