The On-Line Encyclopedia of Integer Sequences (OEIS)

Revision History for A088839

(Bold, blue-underlined text is an addition; faded, red-underlined text is a ~~deletion~~.)
Showing entries 1-10 | older changes

A088839

Numerator of sigma(4n)/sigma(n).
(history; published version)

#21 by Michel Marcus at Fri Jan 06 06:33:30 EST 2023

STATUS

reviewed

approved

#20 by Joerg Arndt at Fri Jan 06 05:40:57 EST 2023

STATUS

proposed

reviewed

#19 by Amiram Eldar at Fri Jan 06 03:31:08 EST 2023

STATUS

editing

proposed

#18 by Amiram Eldar at Fri Jan 06 03:26:42 EST 2023

FORMULA

From _Amiram Eldar, _, Jan 06 2023: (Start)

#17 by Amiram Eldar at Fri Jan 06 03:25:57 EST 2023

FORMULA

From Amiram Eldar, Jan 06 2023: (Start)

a(n) = numerator(A193553(n)/A000203(n)).

Asymptotic mean: Limit_{m->oo} (1/m) * Sum_{k=1..m} a(k)/A088840(k) = 3*A065442 + 1 = 5.820085... . - _Amiram Eldar_, Jan 06 2023(End)

CROSSREFS

Cf. A000203, A038712, A088837, A088838, A088841, A080278, A000203A193553.

#16 by Amiram Eldar at Fri Jan 06 02:54:48 EST 2023

LINKS

<a href="/index/Si#SIGMAN">Index entries for sequences related to sigma(n)</a>.

#15 by Amiram Eldar at Fri Jan 06 02:54:36 EST 2023

FORMULA

Asymptotic mean: Limit_{m->oo} (1/m) * Sum_{k=1..m} a(k)/A088840(k) = 3*A065442 + 1 = 5.820085... . - Amiram Eldar, Jan 06 2023

CROSSREFS

Cf. A006519, A065442, A096268.

STATUS

approved

editing

#14 by Joerg Arndt at Sun Nov 19 02:56:12 EST 2017

STATUS

proposed

approved

#13 by Robert Israel at Sun Nov 19 02:44:46 EST 2017

STATUS

editing

proposed

#12 by Robert Israel at Sun Nov 19 02:44:38 EST 2017

FORMULA

a(n) = (8*A006519(n)-1)/(1+2*A096268(n)). - Robert Israel, Nov 19 2017

MAPLE

f:= proc(n) local m;

m:= padic:-ordp(n, 2);

if m::odd then (2^(m+3)-1)/3 else 2^(m+3)-1 fi

end proc:

map(f, [$1..200]); # Robert Israel, Nov 19 2017

CROSSREFS

Cf. A006519, A096268.

STATUS

approved

editing