login
This site is supported by donations to The OEIS Foundation.

 

Logo

Please make a donation to keep the OEIS running. We are now in our 55th year. In the past year we added 12000 new sequences and reached 8000 citations (which often say "discovered thanks to the OEIS"). We need to raise money to hire someone to manage submissions, which would reduce the load on our editors and speed up editing.
Other ways to donate

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A294567 a(n) = Sum_{d|n} d^(1 + 2*n/d). 2
1, 9, 28, 97, 126, 588, 344, 2049, 2917, 6174, 1332, 53764, 2198, 52320, 258648, 430081, 4914, 2463429, 6860, 8352582, 15181712, 8560308, 12168, 242240964, 48843751, 134606598, 1167064120, 1651526120, 24390, 14202123408, 29792, 25905102849, 94162701936 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

If p is prime, a(p) = 1 + p^3. - Robert Israel, Nov 03 2017

LINKS

Seiichi Manyama, Table of n, a(n) for n = 1..3143

FORMULA

L.g.f.: -log(Product_{k>=1} (1 - k^2*x^k)) = Sum_{n>=1} a(n)*x^n/n. - Ilya Gutkovskiy, Mar 12 2018

MAPLE

f:= n -> add(d^(1+2*n/d), d=numtheory:-divisors(n)):

map(f, [$1..100]); # Robert Israel, Nov 03 2017

PROG

(PARI) a(n) = sumdiv(n, d, d^(1+2*n/d)); \\ Michel Marcus, Nov 02 2017

CROSSREFS

Column k=2 of A294579.

Cf. A292164.

Sequence in context: A001158 A171215 A296601 * A053819 A294287 A085292

Adjacent sequences:  A294564 A294565 A294566 * A294568 A294569 A294570

KEYWORD

nonn

AUTHOR

Seiichi Manyama, Nov 02 2017

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified December 9 09:21 EST 2019. Contains 329877 sequences. (Running on oeis4.)