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 A341414 #32 Apr 04 2021 10:02:07
%S A341414 0,1,3,8,1,5,4,7,7,4,5,1,8,3,1,0,9,7,2,9,5,6,3,3,6,5,9,2,7,9,0,1,3,8,
%T A341414 1,5,4,7,7,4,5,1,8,3,1,0,9,7,2,9,5,6,3,3,6,5,9,2,7,9,0,1,3,8,1,5,4,7,
%U A341414 7,4,5,1,8,3,1,0,9,7,2,9,5,6,3,3,6,5,9,2,7,9
%N A341414 a(n) = (Fibonacci(n)*Lucas(n)) mod 10.
%C A341414 Fibonacci starting with 0,1 and Lucas starting with 2,1.
%C A341414 Blocks of 30 numbers with 10 even and 20 uneven numbers.
%C A341414 Symmetric as a(7-i)=a(8+i) for i=1,2,...,6, and a(22-j)=a(23+j) for j=1..21.
%C A341414 Decimal expansion of 13801675776055042253380279/999000999000999000999000999. - _Jianing Song_, Apr 04 2021
%H A341414 <a href="/index/Rec#order_27">Index entries for linear recurrences with constant coefficients</a>, signature (0,0,1,0,0,-1,0,0,1,0,0,-1,0,0,1,0,0,-1,0,0,1,0,0,-1,0,0,1).
%F A341414 a(n) = (Fibonacci(n)*Lucas(n)) mod 10 = Fibonacci(2*n) mod 10 using Binet's formula for Fibonacci and corresponding formula for Lucas.
%F A341414 a(n) = a(n-30).
%F A341414 a(n) = a(n-3) - a(n-6) + a(n-9) - a(n-12) + a(n-15) - a(n-18) + a(n-21) - a(n-24) + a(n-27).
%F A341414 a(n) = A003893(2*n).
%e A341414 For n=5: a(5) = (Fibonacci(5)*Lucas(5)) mod 10 = (5*11) mod 10 = 55 mod 10 = 5.
%t A341414 Table[Mod[Fibonacci@n*LucasL@n, 10], {n, 0, 100}] (* _Giorgos Kalogeropoulos_, Mar 31 2021 *)
%o A341414 (PARI) a(n) = fibonacci(2*(n%30)) % 10 \\ _Jianing Song_, Apr 04 2021
%Y A341414 Cf. A000032, A000045, A001906, A130893.
%Y A341414 Bisection of A003893.
%K A341414 easy,nonn
%O A341414 0,3
%A A341414 _Jens Rasmussen_, Feb 11 2021