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A374205
The 5-adic valuation of A328845(n), where A328845 is a Fibonacci-based variant of the arithmetic derivative.
8
0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 1, 0, 0, 2, 0, 0, 0, 0, 1, 0, 0, 0, 0, 2, 0, 0, 1, 0, 1, 0, 1, 0, 0, 2, 0, 0, 0, 2, 2, 0, 0, 0, 2, 1, 0, 0, 0, 0, 3, 2, 0, 0, 1, 3, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 2, 2, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 1, 0, 0, 1, 2, 1, 0, 0, 3, 0, 0, 0, 0, 2, 0, 0, 0, 1, 1, 0, 0, 0, 0, 1, 2, 0, 0, 0, 2, 0, 0, 0, 2, 1, 0, 0, 1, 2, 3
OFFSET
2,14
LINKS
FORMULA
a(n) = A112765(A328845(n)).
MATHEMATICA
A374205[n_] := IntegerExponent[n*Total[MapApply[#2*Fibonacci[#]/# &, FactorInteger[n]]], 5];
Array[A374205, 100, 2] (* Paolo Xausa, Dec 16 2024 *)
PROG
(PARI)
A328845(n) = if(n<=1, 0, my(f=factor(n)); n*sum(i=1, #f~, f[i, 2]*fibonacci(f[i, 1])/f[i, 1]));
A374205(n) = valuation(A328845(n), 5);
CROSSREFS
KEYWORD
nonn,changed
AUTHOR
Antti Karttunen, Jul 01 2024
STATUS
approved