%I A060291
%S A060291 7,8,21,60,278,1520,9583
%N A060291 Number of twin Harshads, including overlaps, whose sum is prime and where 
               the 2nd Harshad is <= to a consecutive power of 10 (beginning at 
               10^1).
%F A060291 Generate the twin Harshads whose sum is prime. Count how many there are 
               where the 2nd Harshad in the pair is <= to a consecutive power of 
               10
%e A060291 a(0)=7 because there are 7 pairs of Harshads whose sum is prime and the 
               2nd Harshad in the pair is <= 10; these are 1+2=3, 2+3=5, 3+4=7, 
               5+6=11, 6+7=13, 8+9=17, 9+10=19. (Another sequence does not permit 
               overlapping Harshad numbers.)
%Y A060291 A060288-A060290, A005349, A060159.
%Y A060291 Sequence in context: A143504 A165432 A152043 this_sequence A132899 A051175 
               A058537
%Y A060291 Adjacent sequences: A060288 A060289 A060290 this_sequence A060292 A060293 
               A060294
%K A060291 easy,more,nonn
%O A060291 0,1
%A A060291 Enoch Haga (Enokh(AT)comcast.net), Mar 24 2001