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!)
A293465 a(n) = Sum_{k=0..n} (-1)^k * 2^k * q(k), where q(k) is A000009 (partitions into distinct parts). 2
1, -1, 3, -13, 19, -77, 179, -461, 1075, -3021, 7219, -17357, 44083, -103373, 257075, -627661, 1469491, -3511245, 8547379, -19764173, 47344691, -112038861, 261254195, -611161037, 1435659315, -3329070029, 7743892531, -18025911245, 41566759987, -95872193485 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

LINKS

Vaclav Kotesovec, Table of n, a(n) for n = 0..1000

FORMULA

a(n) ~ (-1)^n * 2^(n-1) * exp(Pi*sqrt(n/3)) / (3^(5/4) * n^(3/4)).

a(n) ~ (-1)^n * 2/3 * 2^n * A000009(n).

MATHEMATICA

Table[Sum[(-1)^k * 2^k * PartitionsQ[k], {k, 0, n}], {n, 0, 30}]

CROSSREFS

Cf. A025147, A293466.

Sequence in context: A158016 A281998 A294676 * A271924 A178712 A273686

Adjacent sequences:  A293462 A293463 A293464 * A293466 A293467 A293468

KEYWORD

sign

AUTHOR

Vaclav Kotesovec, Oct 09 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 May 16 03:46 EDT 2021. Contains 343937 sequences. (Running on oeis4.)