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A235992 Numbers with an even arithmetic derivative, cf. A003415. 10
0, 1, 4, 8, 9, 12, 15, 16, 20, 21, 24, 25, 28, 32, 33, 35, 36, 39, 40, 44, 48, 49, 51, 52, 55, 56, 57, 60, 64, 65, 68, 69, 72, 76, 77, 80, 81, 84, 85, 87, 88, 91, 92, 93, 95, 96, 100, 104, 108, 111, 112, 115, 116, 119, 120, 121, 123, 124, 128, 129, 132, 133 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

COMMENTS

A165560(a(n)) = 0; A003415(a(n)) mod 2 = 0.

For n > 1: A007814(a(n)) <> 1, A006519(a(n)) <> 2.

Union of multiples of 4 and odd numbers with an even number of prime factors with multiplicity. - Charlie Neder, Feb 25 2019

After two initial terms (0 and 1), numbers n such that A086134(n) = 2. - Antti Karttunen, Sep 30 2019

LINKS

Reinhard Zumkeller, Table of n, a(n) for n = 1..10000

MATHEMATICA

Select[Range[0, 133], EvenQ@ If[Abs@ # < 2, 0, # Total[#2/#1 & @@@ FactorInteger[Abs@ #]]] &] (* Michael De Vlieger, Sep 30 2019 *)

PROG

(Haskell)

a235992 n = a235992_list !! (n-1)

a235992_list = filter (even . a003415) [0..]

CROSSREFS

Cf. A235991 (complement).

Union of A327862 and A327864.

Cf. A003415, A086134, A327863, A327865, A327933, A327935.

Sequence in context: A145190 A327907 A177713 * A221865 A004753 A144794

Adjacent sequences:  A235989 A235990 A235991 * A235993 A235994 A235995

KEYWORD

nonn,changed

AUTHOR

Reinhard Zumkeller, Mar 11 2014

STATUS

approved

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Last modified October 14 14:06 EDT 2019. Contains 328017 sequences. (Running on oeis4.)