The On-Line Encyclopedia of Integer Sequences (OEIS)

Revision History for A342460 (Bold, blue-underlined text is an addition; faded, red-underlined text is a ~~deletion~~.)
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A342460

a(n) = 1 if n > 1 and is divisible by the sum of its prime factors (with repetition), otherwise 0.
(history; published version)

#13 by N. J. A. Sloane at Tue Mar 23 16:16:56 EDT 2021

STATUS

proposed

approved

#12 by Michael De Vlieger at Fri Mar 19 22:25:48 EDT 2021

STATUS

editing

proposed

#11 by Michael De Vlieger at Fri Mar 19 22:25:26 EDT 2021

MATHEMATICA

Array[Boole[Mod[#, Total@ Flatten[ConstantArray[#1, #2] & @@@ FactorInteger[#]]] == 0] - Boole[# == 1] &, 105] (* Michael De Vlieger, Mar 19 2021 *)

STATUS

proposed

editing

#10 by Antti Karttunen at Fri Mar 19 16:11:34 EDT 2021

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editing

proposed

#9 by Antti Karttunen at Fri Mar 19 03:56:35 EDT 2021

LINKS

Antti Karttunen, <a href="/A342460/b342460.txt">Table of n, a(n) for n = 1..65537</a>

STATUS

approved

editing

#8 by Susanna Cuyler at Thu Mar 18 22:57:09 EDT 2021

STATUS

proposed

approved

#7 by Antti Karttunen at Thu Mar 18 21:19:23 EDT 2021

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editing

proposed

#6 by Antti Karttunen at Thu Mar 18 21:19:05 EDT 2021

FORMULA

a(1) = 0; and for n > 1, a(n) = [0=A238525(n)], where [ ] is the Iverson bracket.

CROSSREFS

Cf. A001414, A010051, A036844, A046346, A238525.

STATUS

proposed

editing

#5 by Antti Karttunen at Thu Mar 18 21:16:30 EDT 2021

STATUS

editing

proposed

#4 by Antti Karttunen at Thu Mar 18 21:15:53 EDT 2021

COMMENTS

Characteristic function of A036844. a(n) - A010051(n) gives the characteristic function for A046346.

CROSSREFS

Cf. A001414, A010051, A036844, A046346.