login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A300549 a(n) = [x^n] Product_{d|n} (1 + x^d)/(1 - x^d). 2
1, 2, 4, 4, 10, 4, 28, 4, 36, 14, 44, 4, 284, 4, 60, 64, 202, 4, 616, 4, 732, 88, 92, 4, 5740, 22, 108, 112, 1404, 4, 10672, 4, 1828, 136, 140, 144, 42622, 4, 156, 160, 22940, 4, 28024, 4, 3420, 3172, 188, 4, 266524, 30, 4344, 208, 4764, 4, 58600, 224, 60204, 232, 236, 4, 3464272, 4, 252, 6052, 27338, 264 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Table of n, a(n) for n=0..65.

Index entries for sequences related to partitions

FORMULA

a(n) = 4 if n is a prime (A000040).

MATHEMATICA

Table[SeriesCoefficient[Product[(1 + Boole[Mod[n, k] == 0] x^k)/(1 - Boole[Mod[n, k] == 0] x^k), {k, 1, n}], {x, 0, n}], {n, 0, 65}]

CROSSREFS

Cf. A000040, A015128, A018818, A033630, A300547, A300548.

Sequence in context: A151712 A253827 A186987 * A038043 A126138 A247570

Adjacent sequences:  A300546 A300547 A300548 * A300550 A300551 A300552

KEYWORD

nonn

AUTHOR

Ilya Gutkovskiy, Mar 08 2018

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 May 26 02:56 EDT 2020. Contains 334613 sequences. (Running on oeis4.)