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A374203
The 3-adic valuation of A328845(n), where A328845 is a Fibonacci-based variant of the arithmetic derivative.
4
0, 0, 0, 0, 0, 0, 1, 1, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 3, 0, 0, 0, 0, 3, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 0, 0, 0, 0, 1, 0, 3, 0, 0, 0, 1, 0, 0, 0, 1, 1, 1, 1, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 1, 3, 0, 0, 0, 1, 0, 0, 0, 0, 1, 2, 1, 0, 0, 1, 0, 0, 0, 1, 1, 0, 0, 0, 0, 0, 2, 0, 4
OFFSET
2,21
LINKS
FORMULA
a(n) = A007949(A328845(n)).
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]));
A374203(n) = valuation(A328845(n), 3);
CROSSREFS
Cf. A007949, A328845, A374121, A374122 (after its 2 initial terms, gives the indices of nonzero terms in this sequence).
Sequence in context: A320179 A035656 A325675 * A279948 A264009 A281155
KEYWORD
nonn
AUTHOR
Antti Karttunen, Jul 01 2024
STATUS
approved