A272389 Longest side of primitive Heronian tetrahedron.
117, 160, 203, 225, 318, 319, 319
Offset: 1
Examples
see A272388
Crossrefs
Cf. A272388
Programs
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Mathematica
aMax=360(*WARNING:takes a long time*); heron=1/4Sqrt[(#1+#2+#3)(-#1+#2+#3)(#1-#2+#3)(#1+#2-#3)]&; cayley=1/24Sqrt[2Det[{ {0,1,1,1,1}, {1,0,#1^2,#2^2,#6^2}, {1,#1^2,0,#3^2,#5^2}, {1,#2^2,#3^2,0,#4^2}, {1,#6^2,#5^2,#4^2,0} }]]&; Do[ S1=heron[a,b,c]; If[S1//IntegerQ//Not,Continue[]]; Do[ S2=heron[a,e,f]; If[S2//IntegerQ//Not,Continue[]]; Do[ If[GCD[a, b, c, d, e, f] > 1, Continue[]]; If[b==e&&c>f||b==f&&c>e,Continue[]]; S3=heron[b,d,f]; If[S3//IntegerQ//Not,Continue[]]; S4=heron[c,d,e]; If[S4//IntegerQ//Not,Continue[]]; V=cayley[a,b,c,d,e,f]; If[V//IntegerQ//Not,Continue[]]; If[V==0,Continue[]]; a//Sow(*{a,b,c,d,e,f,S1,S2,S3,S4,V}//Sow*); ,{d,Sqrt[((b^2-c^2+e^2-f^2)/(2a))^2+4((S1-S2)/a)^2]//Ceiling,Min[a,Sqrt[((b^2-c^2+e^2-f^2)/(2a))^2+4((S1+S2)/a)^2]]}]; ,{e,a-b+1,b},{f,a-e+1,b}]; ,{a,117,aMax},{b,a/2//Ceiling,a},{c,a-b+1,b}]//Reap//Last//Last
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