%I A003988
%S A003988 1,2,0,3,1,0,4,1,0,0,5,2,1,0,0,6,2,1,0,0,0,7,3,1,1,0,0,0,8,3,2,1,0,0,0,
%T A003988 0,9,4,2,1,1,0,0,0,0,10,4,2,1,1,0,0,0,0,0,11,5,3,2,1,1,0,0,0,0,0,12,5,
%U A003988 3,2,1,1,0,0,0,0,0,0,13,6,3,2,1,1,1,0,0,0,0,0,0,14,6,4,2,2,1,1,0,0,0,0
%N A003988 Triangle with subscripts (1,1),(2,1),(1,2),(3,1),(2,2),(1,3), etc. in
which entry (i,j) is [ i/j ].
%C A003988 Another version of A010766.
%F A003988 T(n,k) = sum_{i=1}^k A077049(n,i). G.f. sum_{k>0} x^k y^k/(1-x^k) / (1-x)
= sum_{k>0} x^k y / (1 - x^k y) / (1-x) = sum_{k>0} x^k sum_{d|k}
y^d / (1-x) = A(x,y)/(1-x) where A(x,y) is the g.f. of A077049. -
Frank Adams-Watters (FrankTAW(AT)Netscape.net), Jan 28 2006
%Y A003988 Cf. A003056, A049581, A003991, A004247.
%Y A003988 Row sums are in A006218. Antidiagonal sums are in A002541.
%Y A003988 Sequence in context: A070679 A127374 A098862 this_sequence A144257 A074650
A144955
%Y A003988 Adjacent sequences: A003985 A003986 A003987 this_sequence A003989 A003990
A003991
%K A003988 tabl,nonn,easy,nice
%O A003988 1,2
%A A003988 Marc LeBrun (mlb(AT)well.com)
%E A003988 More terms from James A. Sellers (sellersj(AT)math.psu.edu)
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