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 A379116 #13 Dec 16 2024 08:47:26 %S A379116 0,1,5,10,12,15,20,25,28,30,32,35,39,40,44,45,50,51,54,55,60,65,70,75, %T A379116 76,80,85,87,90,91,92,95,100,104,105,110,111,115,119,120,123,124,125, %U A379116 126,130,135,136,140,143,144,145,150,155,159,160,165,170,172,175,180,183,185,187,188,190,195,198,200,203,205 %N A379116 Numbers k for which A328845(k) is a multiple of 5, where A328845 is the first Fibonacci based variant of arithmetic derivative. %C A379116 A multiplicative semigroup: if m and n are in the sequence, then so is m*n. %H A379116 Antti Karttunen, <a href="/A379116/b379116.txt">Table of n, a(n) for n = 1..20000</a> %t A379116 A379116Q[k_] := If[k <= 1, True, Divisible[k*Total[MapApply[#2*Fibonacci[#]/# &, FactorInteger[k]]], 5]]; %t A379116 Select[Range[0, 300], A379116Q] (* _Paolo Xausa_, Dec 16 2024 *) %o A379116 (PARI) is_A379116 = A379117; %Y A379116 Positions of multiples of 5 in A328845, of nonzero terms in A374205, of 0's in A379115. %Y A379116 Cf. A379117 (characteristic function). %Y A379116 Cf. also A374046, A374122. %K A379116 nonn %O A379116 1,3 %A A379116 _Antti Karttunen_, Dec 15 2024