# Greetings from The On-Line Encyclopedia of Integer Sequences! http://oeis.org/ Search: id:a336752 Showing 1-1 of 1 %I A336752 #21 Aug 17 2020 22:44:54 %S A336752 1,2,1,3,1,5,1,7,3,1,1,3,1,1,1,7,1,1,1,9,1,2,1,3,1,2,1,9,1,3,1,1,1,3, %T A336752 1,7,1,4,1,1,1,4,1,3,1,4,1,7,1,5,1,3,1,5,1,9,1,6,1,1,1,6,2,7,1,1,1,7, %U A336752 1,3,1,7,1,9,1,8,1,3,1,8,2,9,1,7,1,1,1,0,2,1,1,0,1,3,1,1,1,0,1,7 %N A336752 The 'Look and Say' sequence of the concatenation of the prime numbers A033308. %C A336752 Concatenate all the decimal prime numbers, see A033308, then describe the resulting infinite string using the 'Look and Say' method of A005150. %H A336752 J. H. Conway and Brady Haran, Look-and-Say Numbers (2014), Numberphile video. %H A336752 Wikipedia, Look-and-say sequence. %e A336752 The concatenation of the primes starts "23571113171923293137...". %e A336752 a(1) = 1, a(2) = 2 as there is one '2' at the start of the string. %e A336752 a(9) = 3, a(10) = 1 as the primes '11' and '13' from the substring '1113'. which starts with three 1's. %Y A336752 Cf. A033308, A005150, A001155, A056815, A000040. %K A336752 nonn,base %O A336752 1,2 %A A336752 _Scott R. Shannon_, Aug 15 2020 # Content is available under The OEIS End-User License Agreement: http://oeis.org/LICENSE