Strobogrammatic number Strobogrammatic number A strobogrammatic number is a number whose numeral is rotationally symmetric, so that it appears the same when rotated 180 degrees. In other words, the numeral looks the same right-side up and upside down (e.g., 69, 96, 1001). A strobogrammatic prime is a strobogrammatic number that is also a prime number, i.e., a number that is only divisible by one and itself (e.g., 11). It is a type of ambigram, words and numbers that retain their meaning when viewed from a different perspective, such as palindromes. When written using standard characters (ASCII), the numbers, 0, 1, 8 are
Infinity Bridge when the river surface is flat calm, the twin arches together with their reflection in the river appear as an infinity symbol ∞, and it is this effect that inspired its name. The bridge was constructed in 18 months between June 2007 and December 2008 by site constructor Balfour Beatty Regional Civil Engineering and steel fabricator Cleveland Bridge & Engineering Company with White Young Green managing the whole project. At the start of construction, a temporary jetty was built on the south bank to enable the building of a cofferdam for the safe construction of the central pier. In April