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A174888 Triangle read by rows. Row sums = Mobius function A008683, row counts of nonzero elements = A074206.

%I A174888 #6 Aug 10 2015 00:34:08
%S A174888 1,0,-1,0,-1,0,1,-1,0,0,0,-1,0,0,0,1,-1,1,0,0,0,0,-1,0,0,0,0,0,1,-1,1,
%T A174888 -1,0,0,0,0,1,-1,0,0,0,0,0,0,0,1,-1,1,0,0,0,0,0,0,0,0,-1,0,0,0,0,0,0,
%U A174888 0,0,0,1,-1,1,-1,1,-1,1,-1,0,0,0,0,0,-1,0,0,0,0,0,0,0,0,0,0,0,1,-1,1,0,0
%N A174888 Triangle read by rows. Row sums = Mobius function A008683, row counts of nonzero elements = A074206.
%C A174888 This table cannot be completed as a triangle beyond row 95 because the ordered factorization value for 96 is 112, which is greater than the row length 96. Values in the first column are either zero or one, and are chosen so that the number of nonzero elements in each row equals A074206 while rows sums equals A008683. The row indices for nonzero elements in the 1st column are A174891.
%F A174888 First column = A174889.
%F A174888 Beginning from the second column: a(n)=if k<=A074206 then ((-1)^(k+1)) else 0.
%e A174888 Table begins:
%e A174888 n\k|....1....2....3....4....5....6....7....8....9...10
%e A174888 ---|--------------------------------------------------
%e A174888 1..|....1
%e A174888 2..|....0...-1
%e A174888 3..|....0...-1....0
%e A174888 4..|....1...-1....0....0
%e A174888 5..|....0...-1....0....0....0
%e A174888 6..|....1...-1....1....0....0....0
%e A174888 7..|....0...-1....0....0....0....0....0
%e A174888 8..|....1...-1....1...-1....0....0....0....0
%e A174888 9..|....1...-1....0....0....0....0....0....0....0
%e A174888 10.|....1...-1....1....0....0....0....0....0....0....0
%e A174888 Notice that the 30th row begins with a zero:
%e A174888 0,-1,1,-1,1,-1,1,-1,1,-1,1,-1,1,-1
%Y A174888 Cf. A008683, A074206, A174889, A174891, A174892.
%K A174888 sign,tabl
%O A174888 1,1
%A A174888 _Mats Granvik_, Apr 01 2010