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A049251 Smallest nonnegative value taken on by 12x^2 - ny^2 for an infinite number of integer pairs (x, y). 0
3, 4, 0, 8, 3, 6, 5, 4, 3, 2, 1, 0, 12, 12, 12, 12, 3, 12, 12, 12, 3, 12, 1, 12, 3, 4, 0, 12, 3, 12, 12, 12, 3, 12, 12, 12, 11, 10, 9, 8, 3, 6, 5, 4, 3, 2, 1, 0, 12, 12, 12, 12, 3, 12, 5, 12, 3, 2, 1, 12, 12, 12, 12, 12, 3, 12, 5, 12, 3, 12, 1, 12, 3, 4, 0, 12, 3, 12, 12, 12, 3, 12, 1, 12 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

LINKS

Table of n, a(n) for n=1..84.

MATHEMATICA

p = 12; f[n_, z_] := FindInstance[x > 0 && y > 0 && p*x^2 - n*y^2 == z, {x, y}, Integers, 1]; a[n_] := For[z = 0, z <= p, z = z + GCD[n, p], fz = TimeConstrained[f[n, z], 300]; fz = If[fz === $Aborted, {{x -> Null, y -> Null}}, fz]; If[fz =!= {}, Print["a(", n, ") = ", z, " {x, y} = ", {x, y} /. fz[[1]]]; Return[z]]]; Table[a[n], {n, 1, 84}] (* Jean-Fran├žois Alcover, Oct 11 2016 *)

CROSSREFS

Sequence in context: A011338 A214024 A215079 * A308642 A158674 A213280

Adjacent sequences:  A049248 A049249 A049250 * A049252 A049253 A049254

KEYWORD

nonn

AUTHOR

David W. Wilson, Dec 11 1999

STATUS

approved

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Last modified April 6 21:24 EDT 2020. Contains 333286 sequences. (Running on oeis4.)