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

 

Logo

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 56th year, we are closing in on 350,000 sequences, and we’ve crossed 9,700 citations (which often say “discovered thanks to the OEIS”).

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A302580 Numbers k such that the coefficient of x^k in the expansion of Ramanujan's function R(x) = Sum_{i>=0} x^(i*(i+1)/2)/Product_{j=1..i} (1 + x^j) is zero. 0
6, 9, 11, 16, 20, 21, 23, 27, 29, 30, 31, 33, 34, 36, 37, 38, 41, 44, 46, 49, 53, 56, 58, 59, 60, 61, 63, 64, 65, 66, 71, 72, 79, 80, 81, 82, 85, 86, 91, 93, 94, 96, 97, 98, 102, 104, 106, 107, 110, 111, 114, 115, 116, 120, 121, 122, 124, 128, 129, 131, 133, 135, 136, 137, 141, 142, 146, 148 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Numbers k such that number of partitions of k into distinct parts with even rank equals number of partitions of k into distinct parts with odd rank (the rank of a partition is its largest part minus the number of parts).

LINKS

Table of n, a(n) for n=1..68.

Index entries for sequences related to partitions

MATHEMATICA

Flatten[Position[nmax = 150; Rest[CoefficientList[Series[Sum[x^(i (i + 1)/2)/Product[(1 + x^j), {j, 1, i}], {i, 0, nmax}], {x, 0, nmax}], x]], 0]]

CROSSREFS

Cf. A003406, A117192, A117193.

Sequence in context: A315950 A026614 A202137 * A031256 A032730 A275274

Adjacent sequences:  A302577 A302578 A302579 * A302581 A302582 A302583

KEYWORD

nonn

AUTHOR

Ilya Gutkovskiy, Apr 10 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 November 29 21:32 EST 2021. Contains 349416 sequences. (Running on oeis4.)