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!)
A055413 Number of points in Z^7 of norm <= n. 6
1, 15, 953, 12435, 88273, 394691, 1405325, 4031123, 10248133, 23120727, 48218513, 93417543, 172039681, 299505299, 503363697, 813950491, 1279144845, 1950568311, 2912136485, 4244109647, 6080556217, 8545686087, 11835454865 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,2

LINKS

Andrew Howroyd, Table of n, a(n) for n = 0..500

FORMULA

a(n) = [x^(n^2)] theta_3(x)^7/(1 - x), where theta_3() is the Jacobi theta function. - Ilya Gutkovskiy, Apr 14 2018

CROSSREFS

Column k=7 of A302997.

Sequence in context: A136419 A231121 A103639 * A067408 A274713 A229840

Adjacent sequences:  A055410 A055411 A055412 * A055414 A055415 A055416

KEYWORD

nonn

AUTHOR

David W. Wilson

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 5 17:28 EST 2021. Contains 349557 sequences. (Running on oeis4.)