A105152 - OEIS

A105152

Number of sum of squares representations of n^2 in n dimensions disregarding order and sign.

1, 1, 1, 2, 2, 4, 9, 13, 25, 52, 94, 195, 354, 691, 1341, 2514, 4746, 8984, 16639, 31031, 57421, 105091, 192266, 349765, 632223, 1138114, 2043082, 3642712, 6474196, 11462149, 20189285, 35427948, 61987644, 107928280, 187336851, 324080969, 558451251, 959214488

(list; graph; refs; listen; history; text; internal format)

OFFSET

0,4

LINKS

David A. Corneth, Table of n, a(n) for n = 0..500 (first 201 terms from Alois P. Heinz)

EXAMPLE

a(5)=4 since we can write 5^2 as 0^2+0^2+0^2+0^2+5^2, 0^2+0^2+0^2+3^2+4^2, 0^2+1^2+2^2+2^2+4^2, 2^2+2^2+2^2+2^2+3^2.

MATHEMATICA

<< NumberTheory`NumberTheoryFunctions`; Table[Length@SumOfSquaresRepresentations[k, k^2], {k, 16}]

CROSSREFS

Main diagonal of A255212.

Sequence in context: A351351 A160126 A257515 * A066346 A175390 A054233

Adjacent sequences: A105149 A105150 A105151 * A105153 A105154 A105155

KEYWORD

nonn

AUTHOR

Wouter Meeussen, Apr 10 2005

EXTENSIONS

a(18)-a(20) from Robert G. Wilson v, Apr 12 2005

a(0), a(21)-a(37) from Alois P. Heinz, Feb 16 2015

STATUS

approved