A191866 Numbers n such that n = (a+b)*c = a*b+c for some a > b > c > 1, with gcd(a,b) = gcd(b,c) = 1.

14, 33, 39, 60, 84, 95, 110, 138, 155, 189, 217, 248, 258, 259, 315, 360, 390, 399, 473, 504, 530, 539, 564, 584, 663, 754, 770, 819, 869, 885, 897, 1005, 1008, 1053, 1110, 1139, 1278, 1292, 1360, 1378, 1425, 1463, 1580, 1615, 1743, 1802, 1840, 1884, 1914, 1919, 1974

Offset

1,1

Comments

A proper subset of A191676.

Links

Table of n, a(n) for n=1..51.

Mathematica

mx = 2000; lmt = Floor[9 Sqrt[mx]/2]; lst = {}; Do[ If[ GCD[a, b] == 1 && GCD[b, c] == 1 && a*b + c == (a + b) c < mx, AppendTo[ lst, a*b + c]], {a, 4, lmt}, {b, 3, a - 1}, {c, 2, b - 1}]; lst = Sort@ lst

Crossrefs

Cf. A191676.

Sequence in context: A261560 A250186 A191676 * A162279 A367346 A090090

Adjacent sequences: A191863 A191864 A191865 * A191867 A191868 A191869

Keyword

nonn

Author

Robert G. Wilson v, Jun 19 2011

Status

approved