The On-Line Encyclopedia of Integer Sequences (OEIS)

Revision History for A351603 (Bold, blue-underlined text is an addition; faded, red-underlined text is a ~~deletion~~.)
Showing entries 1-10 | older changes

A351603

a(n) = n^5 * Sum_{d^2|n} 1 / d^5.
(history; published version)

#28 by Michel Marcus at Mon Nov 14 01:39:26 EST 2022

STATUS

reviewed

approved

#27 by Joerg Arndt at Mon Nov 14 00:47:48 EST 2022

STATUS

proposed

reviewed

#26 by Amiram Eldar at Sun Nov 13 16:16:26 EST 2022

STATUS

editing

proposed

#25 by Amiram Eldar at Sun Nov 13 15:48:41 EST 2022

FORMULA

Sum_{k=1..n} a(k) ~ c * n^6, where c = zeta(7)/6 = 0.168058... . - Amiram Eldar, Nov 13 2022

MATHEMATICA

f[p_, e_] := p^5*(p^(5*e) - p^(5*Floor[(e - 1)/2]))/(p^5 - 1); a[1] = 1; a[n_] := Times @@ f @@@ FactorInteger[n]; Array[a, 30] (* Amiram Eldar, Nov 13 2022 *)

CROSSREFS

Cf. A013665.

STATUS

approved

editing

#24 by Joerg Arndt at Fri Feb 25 11:53:37 EST 2022

STATUS

reviewed

approved

#23 by Michel Marcus at Fri Feb 25 11:51:52 EST 2022

STATUS

proposed

reviewed

#22 by Sebastian Karlsson at Fri Feb 25 10:00:54 EST 2022

STATUS

editing

proposed

#21 by Sebastian Karlsson at Fri Feb 25 09:57:05 EST 2022

FORMULA

Multiplicative with a(p^e) = p^5*(p^(5*e) - p^(5*floor((e-1)/2)))/(p^5 - 1). - Sebastian Karlsson, Feb 25 2022

KEYWORD

nonn,mult,new

STATUS

approved

editing

#20 by Hugo Pfoertner at Tue Feb 15 12:25:30 EST 2022

STATUS

reviewed

approved

#19 by Andrew Howroyd at Tue Feb 15 12:25:07 EST 2022

STATUS

proposed

reviewed