A297207 3d-congruent numbers: positive integers n for which there exists a trirectangular tetrahedron having volume n and rational areas and sides.

13, 85, 104, 175, 308, 351, 490, 680, 832, 1400, 1625, 2295, 2464, 2808, 3179, 3920, 4459, 4725, 5440, 6656, 8316, 9295, 9477, 9724, 10625, 11200, 13000, 13230, 13475, 17303, 18360, 19712, 19760, 21875, 22464, 25432, 28561, 29155, 31360, 35672, 37800, 38500, 43520, 43875

Offset: 1

Author

Ralf Steiner, Dec 27 2017

Keywords

• nonn

Comments

Ordered list of numbers A295507(i)*j^3 with i,j positive integers.

Examples

			a(1) = 13 = 13*1^3 = A295507(1)*A000578(1) is the volume of the trirectangular tetrahedron with sides: {240, 117, 44, 125, 244, 267}*1^3/15840.
a(3) = 104 = 13*2^3 = A295507(1)*A000578(2) is the volume of the trirectangular tetrahedron with sides: {240, 117, 44, 125, 244, 267}*2^3/15840.
		

Links

• Eric Weisstein's World of Mathematics, Trirectangular Tetrahedron

Crossrefs

Cf. A295507, A000578 (cubes).