A014456 Numbers represented by quadratic form with Gram matrix [ 2, 1, 0; 1, 3, 1; 0, 1, 2 ].

0, 2, 3, 4, 7, 8, 10, 11, 12, 15, 16, 18, 19, 20, 23, 24, 26, 27, 28, 31, 32, 34, 35, 36, 39, 40, 42, 43, 44, 47, 48, 50, 51, 52, 55, 58, 59, 60, 63, 64, 66, 67, 68, 71, 72, 74, 75, 76, 79, 80, 82, 83, 84, 87, 88, 90, 91, 92, 95, 96, 98, 99, 100, 103, 104, 106, 107, 108, 111

Offset

1,2

Links

Table of n, a(n) for n=1..69.

G. Nebe and N. J. A. Sloane, Home page for this lattice

Maple

L := [seq(0, i=1..1)]: for x from -20 to 20 do for y from -20 to 20 do for z from -20 to 20 do if member(2*x^2+2*x*y+3*y^2+2*y*z+2*z^2, L)=false then L := [op(L), 2*x^2+2*x*y +3*y^2+2*y*z+2*z^2] fi: od: od: od: L2 := sort(L): for i from 1 to 100 do printf(`%d, `, L2[i]) od:

Crossrefs

Sequence in context: A302123 A286337 A047547 * A349152 A089190 A306677

Adjacent sequences: A014453 A014454 A014455 * A014457 A014458 A014459

Keyword

nonn

Author

N. J. A. Sloane.

Extensions

More terms from James A. Sellers, May 31 2000

Status

approved