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A327273
An upper bound sequence for A327272.
2
1, 5, 105, 425, 144925, 580125, 243697125, 46420625, 253459513125
OFFSET
0,2
COMMENTS
a(n) can be calculated by a faster algorithm than that for A327272(n). It gives a small (but not necessarily smallest) positive determinant with top row [1,2,2^2,...,2^n] and all entries integers, and rows orthogonal. Note that a(n) = A327272(n) for n=0,1 and 3. See Pinner and Smyth link below for both algorithms, and more details of the sequences.
EXAMPLE
a(2) = 105 since the algorithm for a(n) produces the determinant([[1,2,4],[2,-1,0],[4,8,-5]]) = 105, having top row [1,2,2^2] and all rows orthogonal.
CROSSREFS
Sequence in context: A057016 A193340 A083252 * A034225 A273966 A114481
KEYWORD
nonn,more
AUTHOR
STATUS
approved