A232820 Imaginary part of the sum over the n-th powers of all Gaussian integers in the n X n base square in the first quadrant.

1, 18, 144, 0, -28200, -814968, -15203328, 0, 16696909080, 893794451000, 25789252433472, 0, -54804262577596532, -4044941639317807200, -161017938434267136000, 0, 621130358284578576358416, 59512584052525004199214632, 3008072527724272784969384000, 0

Offset

1,2

Links

Colin Barker, Table of n, a(n) for n = 1..200

Formula

Conjecture: a(4n) = 0. - Michel Marcus, Nov 09 2014

Mathematica

g[n_] := Sum[(a + b I)^n, {a, 1, n}, {b, 1, n}]; Table[Im[g[n]], {n, 33}]

Prog

(PARI) vector(100, n, imag(sum(x=1, n, sum(y=1, n, (x+I*y)^n)))) \\ Colin Barker, Nov 09 2014

Crossrefs

Cf. A230308-A230310, A073763, A232819.

Sequence in context: A299834 A231951 A126513 * A143992 A127408 A008452

Adjacent sequences: A232817 A232818 A232819 * A232821 A232822 A232823

Keyword

sign

Author

José María Grau Ribas, Nov 30 2013

Status

approved