A029596 - OEIS

A029596

Numbers represented by quadratic form with Gram matrix [ 4, 2, 2; 2, 4, 1; 2, 1, 6 ], divided by 2.

0, 2, 3, 4, 6, 7, 8, 9, 10, 12, 13, 14, 15, 16, 18, 21, 22, 23, 24, 26, 27, 28, 29, 31, 32, 33, 34, 35, 36, 38, 39, 40, 41, 42, 43, 44, 46, 47, 48, 49, 50, 51, 52, 53, 54, 56, 57, 58, 59, 60, 61, 62, 63, 64, 66, 67, 68, 69, 71, 72, 73, 74, 75, 76, 77, 78, 81, 82, 83, 84, 86, 87

(list; graph; refs; listen; history; text; internal format)

OFFSET

1,2

LINKS

Table of n, a(n) for n=1..72.

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(4*x^2+4*x*y+4*x*z+4*y^2+2*y*z+6*z^2, L)=false then L := [op(L), 4*x^2 +4*x*y+4*x*z+4*y^2+2*y*z+6*z^2] fi: od: od: od: L2 := sort(L): for i from 1 to 100 do printf(`%d, `, L2[i]/2) od:

CROSSREFS

Sequence in context: A285126 A187388 A232012 * A039160 A175439 A048264

Adjacent sequences: A029593 A029594 A029595 * A029597 A029598 A029599

KEYWORD

nonn,easy

AUTHOR

N. J. A. Sloane.

EXTENSIONS

More terms from James A. Sellers, May 31 2000

STATUS

approved