1,3

Ben Green and Terence Tao, The primes contain arbitrarily long arithmetic progressions

(* Example table from A005115*) a = {{ 1, 2, 2}, {2, 2 + j, 3}, {3, 3 + 2j, 7}, {4, 5 + 6j, 23}, {5, 5 + 6j, 29}, {6, 7 + 30j, 157}, {7, 7 + 150j, 907}, {8, 199 + 210j, 1669}, {9, 199 + 210j, 1879}, {10, 199 + 210j, 2089}, {11, 110437 + 13860j, 249037}, {12, 110437 + 13860j, 262897}} Union[Table[CoefficientList[a[[n, 2]], j][[2]], {n, 1, 12}] /. {2}?2? -> 0]

Cf. A093364, A005115.

Sequence in context: A120950 A055695 A113593 this_sequence A005432 A009422 A057221

Adjacent sequences: A122760 A122761 A122762 this_sequence A122764 A122765 A122766

nonn,uned

Roger Bagula (rlbagulatftn(AT)yahoo.com), Sep 22 2006