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A374202
The 2-adic valuation of A328845(n), where A328845 is a Fibonacci-based variant of the arithmetic derivative.
5
0, 1, 2, 0, 0, 0, 2, 2, 0, 0, 2, 0, 0, 0, 5, 0, 0, 0, 3, 0, 0, 0, 2, 1, 0, 1, 4, 0, 0, 0, 4, 0, 0, 2, 2, 0, 0, 0, 2, 0, 0, 0, 4, 0, 0, 0, 7, 1, 0, 0, 3, 0, 0, 2, 2, 0, 0, 0, 5, 0, 0, 0, 6, 1, 0, 0, 3, 0, 0, 0, 2, 0, 0, 3, 5, 1, 0, 0, 4, 3, 0, 0, 3, 1, 0, 0, 2, 0, 0, 3, 5, 0, 0, 3, 4, 0, 0, 0, 2, 0, 0, 0, 2, 1, 0, 0, 2
OFFSET
2,3
LINKS
FORMULA
a(n) = A007814(A328845(n)).
MATHEMATICA
A374202[n_] := IntegerExponent[n*Total[MapApply[#2*Fibonacci[#]/# &, FactorInteger[n]]], 2];
Array[A374202, 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]));
A374202(n) = valuation(A328845(n), 2);
CROSSREFS
Cf. A007814, A328845, A374045, A374046 (after its 2 initial terms, gives the indices of nonzero terms in this sequence), A374047 (indices of 0's).
Sequence in context: A369309 A216228 A372602 * A291957 A143063 A210703
KEYWORD
nonn,changed
AUTHOR
Antti Karttunen, Jul 01 2024
STATUS
approved