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A120293 Absolute value of numerator of determinant of n X n matrix with M(i,j) = (i+1)/(i+2) if i=j otherwise 1. 13
2, 1, 11, 17, 1, 1, 41, 17, 31, 37, 29, 101, 29, 1, 149, 167, 31, 103, 227, 83, 1, 37, 107, 347, 1, 67, 431, 461, 41, 131, 557, 197, 313, 331, 233, 67, 97, 1, 857, 1, 157, 1, 1031, 359, 281, 293, 1, 1, 661, 229, 1427, 1481, 1, 199, 97, 569, 883, 83, 1, 1949, 503, 173 (list; graph; refs; listen; history; text; internal format)
OFFSET
1,1
COMMENTS
Some a(n) are equal to 1 (n=2,5,6,14,21,25,38,40,42,47,48,53,59,69,70..). All other a(n) are primes that belong to A038907 (33 is a square mod p).
LINKS
FORMULA
a(n) = Abs[numerator[Det[DiagonalMatrix[Table[(i+1)/(i+2)-1,{i,1,n}]]+1]]].
MATHEMATICA
Abs[Numerator[Table[Det[DiagonalMatrix[Table[(i+1)/(i+2)-1, {i, 1, n}]]+1], {n, 1, 70}]]]
CROSSREFS
Sequence in context: A055459 A080958 A138351 * A063624 A101851 A300455
KEYWORD
frac,nonn
AUTHOR
Alexander Adamchuk, Jul 08 2006
STATUS
approved

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Last modified March 28 13:42 EDT 2024. Contains 371254 sequences. (Running on oeis4.)