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 A108046 #21 Apr 12 2025 08:07:24
%S A108046 0,1,1,3,3,7,8,16,22,38,55,98,144,242,381,626,987,1625,2584,4221,6774,
%T A108046 11002,17711,28768,46371,75170,121415,196662,317811,514650,832040,
%U A108046 1346895,2178365,3525566,5702898,9229181,14930352,24160402,39088314,63250220,102334155
%N A108046 Inverse Moebius transform of Fibonacci numbers 0, 1, 1, 2, 3, 5, 8, ...
%H A108046 Indranil Ghosh, <a href="/A108046/b108046.txt">Table of n, a(n) for n = 1..1000</a>
%F A108046 G.f.: Sum_{k>=1} Fibonacci(k-1)*x^k/(1 - x^k). - _Ilya Gutkovskiy_, May 23 2017
%F A108046 a(n) = Sum_{d|n} Fibonacci(d-1). - _Ridouane Oudra_, Apr 11 2025
%e A108046 a(4)=3 because the divisors of 4 are 1,2,4 and the first, second and fourth Fibonacci numbers are 0, 1 and 2, respectively, having sum 3.
%p A108046 with(combinat): with(numtheory): f:=n->fibonacci(n-1): g:=proc(n) local div: div:=divisors(n): sum(f(div[j]),j=1..tau(n)) end: seq(g(n),n=1..45);
%t A108046 a[n_] := DivisorSum[n, Fibonacci[#-1]&]; Array[a, 40] (* _Jean-François Alcover_, Dec 17 2015 *)
%o A108046 (PARI) a(n)=if(n<1,1,sumdiv(n,d,fibonacci(d-1))); /* _Joerg Arndt_, Aug 14 2012 */
%o A108046 (Python)
%o A108046 from sympy import fibonacci, divisors
%o A108046 def a(n): return 1 if n<1 else sum([fibonacci(d - 1) for d in divisors(n)]) # _Indranil Ghosh_, May 23 2017
%Y A108046 Cf. A000045, A007435, A245282.
%K A108046 nonn
%O A108046 1,4
%A A108046 _Emeric Deutsch_, Jun 01 2005