The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 56th year, we are closing in on 350,000 sequences, and we’ve crossed 9,700 citations (which often say “discovered thanks to the OEIS”).

 Hints (Greetings from The On-Line Encyclopedia of Integer Sequences!)
 A243184 Nonnegative numbers of the form 2*x^2+3*x*y-3*y^2. 1
 0, 2, 6, 8, 11, 17, 18, 24, 29, 32, 33, 41, 44, 50, 51, 54, 62, 68, 72, 74, 83, 87, 96, 98, 99, 101, 107, 116, 123, 128, 131, 132, 134, 149, 150, 153, 162, 164, 167, 173, 176, 186, 194, 197, 200, 204, 206, 216, 222, 227, 233, 239, 242, 248, 249, 261, 263, 272, 275, 281, 288, 293, 294, 296, 297 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Discriminant 33. I do not understand why the Mathematica program misses out 0. LINKS R. J. Mathar, Table of n, a(n) for n = 1..1562 N. J. A. Sloane et al., Binary Quadratic Forms and OEIS (Index to related sequences, programs, references) MATHEMATICA Reap[For[n = 0, n <= 300, n++, If[Reduce[2*x^2 + 3*x*y - 3*y^2 == n, {x, y}, Integers] =!= False, Sow[n]]]][[2, 1]] CROSSREFS For primes see A141176. Sequence in context: A136496 A183173 A178931 * A076991 A130205 A054067 Adjacent sequences:  A243181 A243182 A243183 * A243185 A243186 A243187 KEYWORD nonn AUTHOR N. J. A. Sloane, Jun 04 2014 STATUS approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

Last modified December 4 13:00 EST 2021. Contains 349526 sequences. (Running on oeis4.)