%I #7 Jul 12 2012 00:40:01
%S 1,2,2,3,3,2,4,5,4,2,5,6,6,5,2,6,8,7,7,5,2,7,9,10,8,8,5,2,8,11,11,11,
%T 9,9,5,2,9,12,13,13,12,10,9,5,2,10,14,15,15,14,13,11,9,5,2,11,15,17,
%U 17,16,15,14,12,9,5,2,12,17,18,19,19,17,16,15,12,9,5,2,13,18,21
%N Rectangular array: R(n,k)=n+[n/2+1/2]+...+[n/k+1/2], where [ ]=floor and k>=1, by antidiagonals.
%C Limit of n-th row: A056549=(2,5,9,12,17,21,25,...).
%C Row 1: A000027
%C Row 2: A007494
%C R(n,n)=A077024(n)
%C For n>=1, row n is a homogeneous linear recurrence sequence of order A005728(n) with palindromic recurrence coefficients in the sense described at A211701.
%e Northwest corner:
%e 1...2...3...4...5....6....7
%e 2...3...5...6...8....9....11
%e 2...4...6...7...10...11...12
%e 2...5...7...8...11...13...15
%e 2...5...8...9...12...14...16
%t f[n_, m_] := Sum[Floor[n/k + 1/2], {k, 1, m}]
%t TableForm[Table[f[n, m], {m, 1, 20}, {n, 1, 16}]]
%Y Cf. A211701
%K nonn,tabl
%O 1,2
%A _Clark Kimberling_, Apr 20 2012
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