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A295507
1/15840 of the volume of a primitive 3-simplex.
2
13, 175, 490, 85, 308, 13475, 3179, 9295, 19760, 60775, 55315, 225420, 203665, 9724, 512050, 568854, 207740, 252700, 2684396, 8695050, 1221025, 140875, 3121937, 311220, 21390460, 12289004, 17331908, 20074032, 44144100, 18055947, 21118608, 21017325, 40245205, 4418232
OFFSET
1,1
COMMENTS
The volume of every primitive trirectangular tetrahedron with integer sides is divisible by 15840. See A031173 for more comments.
These primitive trirectangular tetrahedrons are primitive 3-simplices.
LINKS
Eric Weisstein's World of Mathematics, Trirectangular Tetrahedron
FORMULA
a(n) = (1/15840)*A031173(n)*A031174(n)*A031175(n)/6.
CROSSREFS
KEYWORD
nonn
AUTHOR
Ralf Steiner, Nov 23 2017
STATUS
approved