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%I #23 Apr 01 2017 04:53:43
%S 1,2,13,224,113335,2222244446,11111333333333555557,
%T 22222222222222444444444444446666668,
%U 1111111111111133333333333333333333333333335555555555555555555577777779
%N Row sums of an analog of Pascal's triangle resulting from replacing addition with concatenation in the construction rule.
%C Number of digits of a(n) is A001405(n).
%C a(2n) begins with exactly A000108(n) 1's. - _Vladimir Shevelev_, Feb 07 2014
%H Alois P. Heinz, <a href="/A236903/b236903.txt">Table of n, a(n) for n = 0..12</a>
%e Triangle begins
%e . 1
%e .
%e . 1 1
%e .
%e . 1 11 1
%e .
%e . 1 111 111 1
%e .
%e . 1 1111 111111 1111 1
%p a:= n-> add((10^binomial(n, k)-1)/9, k=0..n):
%p seq(a(n), n=0..8); # _Alois P. Heinz_, Feb 01 2014
%Y Cf. A001405, A007318.
%K nonn,base
%O 0,2
%A _Vladimir Shevelev_, Feb 01 2014