%I A047947
%S A047947 2,4,2,4,4,4,6,4,2,4,6,6,2,6,4,6,4,6,4,4,6,4,6,10,4,6,6,4,6,4,6,6,4,
%T A047947 2,4,6,8,6,4,2,8,4,10,2,4,10,10,4,6,6,2,10,6,2,6,4,6,12,4,6,10,4,6,
%U A047947 6,6,8,6,10,4,8,6,6,2,6,12,10,2,4,6,6,8,4,2,10,8,6,6,4,8,10,2,6,4,2
%N A047947 Schinzel's rhobar(n), number of distinct lengths of a block of consecutive 
               integers on which a maximum of n primes occurs infinitely often (under 
               the k-tuple conjecture).
%D A047947 Computed by Achim Flammenkamp [ achim(AT)uni-bielefeld.de ].
%e A047947 A block of 21 through 26 consecutive integers may contain at most 7 primes 
               infinitely often. There are 6 possible lengths (21 through 26), so 
               rhobar(7) = 6.
%Y A047947 First differences of A020497.
%Y A047947 Sequence in context: A004020 A143235 A069465 this_sequence A018838 A116982 
               A143271
%Y A047947 Adjacent sequences: A047944 A047945 A047946 this_sequence A047948 A047949 
               A047950
%K A047947 nonn
%O A047947 0,1
%A A047947 David W. Wilson (davidwwilson(AT)comcast.net)