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A358680

a(n) = 1 if the arithmetic derivative of n is even, 0 otherwise.

1, 1, 0, 0, 1, 0, 0, 0, 1, 1, 0, 0, 1, 0, 0, 1, 1, 0, 0, 0, 1, 1, 0, 0, 1, 1, 0, 0, 1, 0, 0, 0, 1, 1, 0, 1, 1, 0, 0, 1, 1, 0, 0, 0, 1, 0, 0, 0, 1, 1, 0, 1, 1, 0, 0, 1, 1, 1, 0, 0, 1, 0, 0, 0, 1, 1, 0, 0, 1, 1, 0, 0, 1, 0, 0, 0, 1, 1, 0, 0, 1, 1, 0, 0, 1, 1, 0, 1, 1, 0, 0, 1, 1, 1, 0, 1, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 1, 1, 0, 0, 1, 1, 0, 0, 1, 1 (list; graph; refs; listen; history; text; internal format)

	OFFSET	`0`
	LINKS	`Antti Karttunen, Table of n, a(n) for n = 0..100000` `Index entries for characteristic functions`
	FORMULA	`a(n) = A059841(A003415(n)).` `a(n) = 1 - A165560(n).` `For n >= 1, a(n) = A121262(n) + A353557(n) = A353494(n) + A353495(n).`
	PROG	`(PARI) A358680(n) = if(n<=1, 1, my(f=factor(n)); 0==((n*sum(i=1, #f~, f[i, 2]/f[i, 1]))%2));`
	CROSSREFS	`Characteristic function of A235992. One's complement of A165560.` `Cf. A003415, A059841, A121262, A353494, A353495, A353557.` `Sequence in context: A095901 A374036 A087049 * A186447 A118009 A113429` `Adjacent sequences: A358677 A358678 A358679 * A358681 A358682 A358683`
	KEYWORD	`nonn`
	AUTHOR	`Antti Karttunen, Dec 07 2022`
	STATUS	`approved`

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Last modified August 22 03:40 EDT 2024. Contains 375354 sequences. (Running on oeis4.)