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A049260 Smallest nonnegative value taken on by n*x^2 - y^2 for an infinite number of integer pairs (x, y). 1
0, 1, 2, 0, 1, 2, 3, 4, 0, 1, 2, 3, 1, 5, 6, 0, 1, 2, 2, 4, 3, 2, 7, 8, 0, 1, 2, 3, 1, 5, 3, 7, 8, 9, 10, 0, 1, 2, 3, 4, 1, 6, 2, 7, 5, 5, 11, 12, 0, 1, 2, 3, 1, 2, 6, 7, 3, 1, 2, 11, 1, 13, 14, 0, 1, 2, 2, 4, 5, 5, 7, 8, 1, 1, 11, 3, 7, 14, 15, 16, 0, 1, 2, 3, 1, 2, 6, 7, 1, 9, 3, 7, 3, 5, 14, 15, 1 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,3

LINKS

Table of n, a(n) for n=1..97.

MATHEMATICA

f[n_, z_] := FindInstance[x > 0 && y > 0 && n*x^2 - y^2 == z, {x, y}, Integers, 1]; a[n_] := For[z = 0, True, z++, fz = f[n, z]; If[fz =!= {}, Print["a(", n, ") = ", z, " {x, y} = ", {x, y} /. fz[[1]]]; Return[z]]]; Array[a, 97] (* Jean-Fran├žois Alcover, Oct 11 2016 *)

CROSSREFS

Sequence in context: A306814 A201079 A241382 * A273294 A053186 A066628

Adjacent sequences:  A049257 A049258 A049259 * A049261 A049262 A049263

KEYWORD

nonn

AUTHOR

David W. Wilson

STATUS

approved

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Last modified June 27 04:37 EDT 2022. Contains 354888 sequences. (Running on oeis4.)