x² + x + 41.Descent was ascent, so the protology of the temple insisted; and indeed, those who were lowered to the mosaic often found their heads spinning with a strange vertigo, for the luminous pattern of the mosaic glimmered galactically, as though descent to the under-earth were ascent rather into heaven and they would reach no solid base, but be loosed at limit of their ropes to fall endlessly out among the primal stars. But the vertigo would fade as the glimmer resolved to the squares of the mosaic, comprising a spiral of integers wherein primes glowed and composites were dark. Streaks and lines were visible therein, marking arithmetic sequences that hinted at some master formula for the primes, whereby each could be generated by the priests in its order; but no such formula had been found in the centuries of the temple’s existence and mayhap never would be. Their highest primes had been found empirically, flashed back along the line of the mosaic’s hieratic explorers, who were out to coil seven-thousand-and-eighty-six now. Camps had been established on the floor, as though it were the wall of some great mountain whereup supplies were being passed, but exploration of the mosaic had this difference: that the priests would not defile its surface, and as supplies passed out to north and south, east and west, having been lowered from above to the center of the spiral, so cess-pots passed back, for raising and emptying on the surface. And ’twas known now that the spiral was enchanted, having infinite surface in finite area, and that all who ventured out on it shrank to match the shrinking squares. The farthest priests, it was calculated, were no bigger than mites, by comparison with their fratres at the center, wherefor they could not signal thereto direct, only by the chain of camps: mites to grasshoppers, grasshoppers to mice, mice to owls, owls to monkeys, monkeys to dwarves, dwarves to men.Leonhard Euler (1707-83).