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This is a Truncated Sphere D18.
The numbering has been done very carefully. Of course, numbers on opposite faces sum to 19. This leads to the fact that the 8 numbers around any of the 3 diameters sum to 76. But the dificulty has been the have the 6 numbers surrounding a spherical zone to sum to 57. It works for all the 8 zones (for instance, in the rendering - the brown one - you can see: 18 + 3 + 13 +11 + 7 + 5 = 57).