|
%I #40 Oct 25 2014 14:15:43
%S 2,1,1,1,1,1,1,1,1,1,1,3,1,1,2,1,1,1,1,1,2,1,2,1,1,1,3,1,1,2,1,1,1,7,
%T 1,1,1,2,1,1,1,2
%N Consider the partition of the positive odd integers into minimal blocks such that concatenation of numbers in each block is a number of the form 3^k*prime, k>=0. Sequence lists numbers of odd integers in the blocks.
%C 3^m, m>=1, is of the considered form 3^k*prime, k=m-1>=0, prime=3.
%C The first blocks of the partition are |1,3|,|5|,|7|,|9|,|11|,|13|,|15|,|17|,|19|,|21|,|23|,|25,27,29|,|31|,|33|,|35,37|,...
%e The 12th block of partition is |25,27,29|, since we have 25=5^2, 2527=7*19^2, 252729=3^2*28081, and only the last number is of the required form. So a(12)=3.
%Y Cf. A103899, A248146.
%K nonn,base,more
%O 1,1
%A _Vladimir Shevelev_, Oct 02 2014
|
