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A135622
16*Area^2 of integer triangles [A070080(n),A070081(n),A070082(n)].
0
3, 15, 48, 35, 63, 128, 63, 135, 243, 240, 320, 99, 231, 275, 495, 384, 576, 768, 143, 351, 455, 819, 975, 560, 896, 1008, 1344, 195, 495, 675, 1215, 735, 1575, 1875, 768, 1280, 1536, 2048, 2304, 255, 663, 935, 1683, 1071, 2295, 2499, 2975, 1008, 1728
OFFSET
1,1
COMMENTS
A070086(n) = round(sqrt(a(n))/4).
FORMULA
a(n)=(u+v+w)*(-u+v+w)*(u-v+w)*(u+v-w), where u=A070080(n), v=A070081(n), w=A070082(n).
EXAMPLE
A070080(4)=1, A070081(4)=3, A070082(4)=3, so a(4)=(1+3+3)*(-1+3+3)*(1-3+3)*(1+3-3)=35.
CROSSREFS
Sequence in context: A163383 A296799 A328111 * A316853 A061316 A124161
KEYWORD
nonn
AUTHOR
Franz Vrabec, Feb 29 2008
STATUS
approved