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%I #21 Apr 26 2022 10:20:01
%S 1,1,-3,-14,-35,-69,-119,-188,-279,-395,-539,-714,-923,-1169,-1455,
%T -1784,-2159,-2583,-3059,-3590,-4179,-4829,-5543,-6324,-7175,-8099,
%U -9099,-10178,-11339,-12585,-13919,-15344,-16863,-18479,-20195,-22014,-23939,-25973,-28119,-30380,-32759,-35259,-37883
%N The r-th term of the n-th row of the following array contains the sum of r successively decreasing integers beginning from n. 0 < r <= n. Sequence contains the leading diagonal.
%F From _R. J. Mathar_, Jul 10 2009: (Start)
%F a(n) = n*(1 + 2*n - n^2)/2 = n - A002411(n-1).
%F G.f.: x*(1 - 3*x - x^2)/(1-x)^4.
%F a(n) = 4*a(n-1) - 6*a(n-2) + 4*a(n-3) - a(n-4). (End)
%e E.g., the row corresponding to 4 contains 4, (3+2),{(1) +(0)+(-1)}, {(-2)+(-3)+(-4)+(-5)} ----> 4,5,0,-14
%e 1
%e 2 1
%e 3 3 -3
%e 4 5 0 -14
%e 5 7 3 -10 -35
%e 6 9 6 -6 -30 -69
%e ...
%e Sequence contains the leading diagonal.
%o (PLT DrScheme)
%o (first (reverse (A110425 n))
%o ;;see A110425 for definition of that function.
%o -- _Joshua Zucker_, May 10 2006
%Y Cf. A110425, A110426.
%K easy,sign
%O 1,3
%A _Amarnath Murthy_, Aug 01 2005
%E More terms from _Joshua Zucker_, May 10 2006
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