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A379115
a(n) = A328845(n) mod 5, where A328845 is the first Fibonacci based variant of arithmetic derivative.
0
0, 0, 1, 2, 4, 0, 2, 3, 2, 2, 0, 4, 0, 3, 3, 0, 2, 2, 3, 1, 0, 3, 4, 2, 2, 0, 4, 4, 0, 4, 0, 4, 0, 4, 1, 0, 4, 2, 1, 0, 0, 1, 2, 2, 0, 0, 2, 3, 3, 2, 0, 0, 4, 3, 0, 0, 3, 1, 2, 1, 0, 1, 4, 1, 2, 0, 1, 3, 1, 2, 0, 4, 4, 3, 1, 0, 0, 1, 4, 1, 0, 1, 3, 2, 1, 0, 2, 0, 4, 4, 0, 0, 0, 4, 3, 0, 4, 2, 3, 3, 0, 1, 1, 2, 0, 0
OFFSET
0,4
LINKS
FORMULA
a(n) = A010874(A328845(n)) = A010874(A374125(n)).
MATHEMATICA
A379115[n_] := If[n <= 1, 0, Mod[n*Total[MapApply[#2*Fibonacci[#]/# &, FactorInteger[n]]], 5]];
Array[A379115, 100, 0] (* Paolo Xausa, Dec 16 2024 *)
PROG
(PARI) A379115(n) = if(n<=1, 0, my(f=factor(n)); (n*sum(i=1, #f~, f[i, 2]*fibonacci(f[i, 1])/f[i, 1]))%5);
CROSSREFS
Cf. A010874, A328845, A374125, A374205, A379116 (positions of 0's), A379117 (their characteristic function).
Sequence in context: A011165 A188672 A228518 * A279647 A028963 A004516
KEYWORD
nonn,new
AUTHOR
Antti Karttunen, Dec 15 2024
STATUS
approved