The On-Line Encyclopedia of Integer Sequences (OEIS)

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Revision History for A195089

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A195089

Numbers k such that (number of prime factors of k counted with multiplicity) less (number of distinct prime factors of k) = 5.
(history; published version)

#30 by Michael De Vlieger at Wed Sep 25 10:28:29 EDT 2024

STATUS

reviewed

approved

#29 by Joerg Arndt at Wed Sep 25 02:35:50 EDT 2024

STATUS

proposed

reviewed

#28 by Amiram Eldar at Wed Sep 25 00:10:12 EDT 2024

STATUS

editing

proposed

#27 by Amiram Eldar at Tue Sep 24 23:54:57 EDT 2024

COMMENTS

The asymptotic density of this sequence is (6/Pi^2) * Sum_{k>=1} f(a(k)) = 0.0118439..., where f(k) = A112526(k) * Product_{p|k} p/(p+1). - Amiram Eldar, Sep 24 2024

CROSSREFS

Cf. A025487, A046660, A059956, A112526, A257851, A261256, A264959.

#26 by Amiram Eldar at Tue Sep 24 23:54:18 EDT 2024

COMMENTS

A046660(a(n)) = 5. - Reinhard Zumkeller, Nov 29 2015

LINKS

<a href="/index/Eu#epf">Index entries for sequences computed from exponents in factorization of n</a>.

FORMULA

A046660(a(n)) = 5. - Reinhard Zumkeller, Nov 29 2015

CROSSREFS

Cf. A060687, A195069, A195086, A195087, A195088, A195090, A195091, A195092, A195093.

A195091, A195092, A195093.

KEYWORD

nonn,easy

STATUS

approved

editing

#25 by Joerg Arndt at Sun Mar 17 02:15:55 EDT 2024

STATUS

editing

approved

#24 by Paolo P. Lava at Sat Mar 16 15:18:08 EDT 2024

MAPLE

op(select(n->bigomega(n)-nops(factorset(n))=5, [$1..3904])); # Paolo P. Lava, Jul 03 2018

STATUS

approved

editing

#23 by Bruno Berselli at Tue Jul 03 11:41:54 EDT 2018

STATUS

proposed

approved

#22 by Michel Marcus at Tue Jul 03 11:26:55 EDT 2018

STATUS

editing

proposed

#21 by Michel Marcus at Tue Jul 03 11:26:53 EDT 2018

NAME

Numbers n k such that (number of prime factors of n k counted with multiplicity) less (number of distinct prime factors of nk) = 5.

MAPLE

op(select(n->bigomega(n)-nops(factorset(n))=5, [$1..3904])); # _Paolo P. Lava_, Jul 03 2018

# Paolo P. Lava, Jul 03 2018

STATUS

proposed

editing