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!)
A333173 a(n) = r_4(n^2 + 1), where r_4(k) is the number of ways of writing k as a sum of 4 squares (A000118). 2
8, 24, 48, 144, 144, 336, 304, 744, 672, 1008, 816, 1488, 1440, 2592, 1584, 2736, 2064, 4320, 3472, 4368, 3216, 6048, 4704, 7776, 4624, 7536, 5424, 10656, 7584, 10128, 7776, 12768, 10416, 15840, 10080, 14736, 10384, 19872, 14736, 18288, 12816, 20904, 16992, 28272 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

LINKS

Amiram Eldar, Table of n, a(n) for n = 0..10000

R. Sitaramachandrarao and P. V. Krishnaiah, On the sums Sigma_{n<=x} A(f(n)) and Sigma_{p<=x} A(f(p)), Journal of Number Theory, Vol. 23, No. 2 (1986), pp. 149-168.

FORMULA

a(n) = A000118(A002522(n)).

EXAMPLE

a(0) = r_4(0^2 + 1) = r_4(1) = A000118(1) = 8.

MATHEMATICA

Table[SquaresR[4, k^2 + 1], {k, 0, 100}]

CROSSREFS

Cf. A000118, A002522 A193432, A193433, A333167, A333169.

Sequence in context: A342062 A319576 A028612 * A068857 A064225 A304844

Adjacent sequences:  A333170 A333171 A333172 * A333174 A333175 A333176

KEYWORD

nonn

AUTHOR

Amiram Eldar, Mar 09 2020

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 September 17 14:07 EDT 2021. Contains 347478 sequences. (Running on oeis4.)