For example, in the ring of Gaussian integers, R_-1, we have the factorizations 2=(1+i)(1-i), 5=(1+2i)(1-2i), 13=(2+3i)(2-3i), 17=(1+4i)(1-4i), 29=(2+5i)(2-5i), ⋮ where all the Gaussian integer factors in brackets above are irreducible elements of the ring of Gaussian integers.

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It was an illusion, of course, generated by Clevinger's predilection for staring fixedly at one side of a question and never seeing the other side at all.

High-definition television (HDTV), now being developed, employs over 1000 scanning lines and produces a supersharp picture.