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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 Vincenzo Librandi, Table of n, a(n) for n = 1..300 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 Cf. A118679, A038907. Sequence in context: A055459 A080958 A138351 * A063624 A101851 A300455 Adjacent sequences:  A120290 A120291 A120292 * A120294 A120295 A120296 KEYWORD frac,nonn AUTHOR Alexander Adamchuk, Jul 08 2006 STATUS approved

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Last modified April 6 12:19 EDT 2020. Contains 333273 sequences. (Running on oeis4.)