%I A138243
%S A138243 1,2,1,2,3,1,1,1,1,1,2,3,5,1,1,1,1,1,1,1,1,2,3,1,7,1,1,1,1,1,1,1,1,1,1,
%T A138243 1,2,3,5,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,2,3,1,1,11,1,1,1,1,1,1,1,1,1,
               1,
%U A138243 1,1,1,1,1,1,1,1,2,3,5,7,1,13,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,1,
               1
%N A138243 Triangle read by rows: Row products give A027642.
%C A138243 Except for the first column, the n:th prime number appears at every A006093:th 
               row, beginning at the A000040:th row in the n:th column.
%F A138243 T(n,k) = if mod(A027642;A000040)=0 then A000040 else 1.
%e A138243 Row products of the first few rows are:
%e A138243 1 = 1
%e A138243 2*1 = 2
%e A138243 2*3*1 = 6
%e A138243 1*1*1*1 = 1
%e A138243 2*3*5*1*1 = 30
%e A138243 1*1*1*1*1*1 = 1
%e A138243 2*3*1*7*1*1*1 = 42
%e A138243 1*1*1*1*1*1*1*1 = 1
%e A138243 2*3*5*1*1*1*1*1*1 = 30
%Y A138243 Cf. A027642, A006093.
%Y A138243 Sequence in context: A094646 A124448 A143343 this_sequence A131796 A131797 
               A145727
%Y A138243 Adjacent sequences: A138240 A138241 A138242 this_sequence A138244 A138245 
               A138246
%K A138243 nonn,tabl
%O A138243 1,2
%A A138243 Mats O. Granvik (mgranvik(AT)abo.fi), Mar 08 2008