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A238753
Squarefree integers D such that Q(sqrt(D)) contains a non-constant arithmetic progression of 5 squares.
0
409, 4688329, 250545884330641, 199554894091303668073201, 231574628370557219024862837633967849, 30240048139343876249762998173442832362876517638009, 330823513952828243573122480536077533156064000139119724642295861921
OFFSET
1,1
COMMENTS
Note that there exists no D such that Q(sqrt{D}) contains a non-constant arithmetic progression of 6 squares.
LINKS
Enrique González-Jiménez and Xavier Xarles, Five squares in arithmetic progression over quadratic fields, arXiv:0909.1663 [math.NT], 2009-2013.
EXAMPLE
For D=409, such an arithmetic progression is 49, 169, 289, 409, 529.
CROSSREFS
Sequence in context: A107625 A061333 A262636 * A157431 A179129 A176598
KEYWORD
nonn
AUTHOR
David Cushing, Mar 04 2014
STATUS
approved