# Greetings from The On-Line Encyclopedia of Integer Sequences! http://oeis.org/ Search: id:a110427 Showing 1-1 of 1 %I A110427 #21 Apr 26 2022 10:20:01 %S A110427 1,1,-3,-14,-35,-69,-119,-188,-279,-395,-539,-714,-923,-1169,-1455, %T A110427 -1784,-2159,-2583,-3059,-3590,-4179,-4829,-5543,-6324,-7175,-8099, %U A110427 -9099,-10178,-11339,-12585,-13919,-15344,-16863,-18479,-20195,-22014,-23939,-25973,-28119,-30380,-32759,-35259,-37883 %N A110427 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 A110427 From _R. J. Mathar_, Jul 10 2009: (Start) %F A110427 a(n) = n*(1 + 2*n - n^2)/2 = n - A002411(n-1). %F A110427 G.f.: x*(1 - 3*x - x^2)/(1-x)^4. %F A110427 a(n) = 4*a(n-1) - 6*a(n-2) + 4*a(n-3) - a(n-4). (End) %e A110427 E.g., the row corresponding to 4 contains 4, (3+2),{(1) +(0)+(-1)}, {(-2)+(-3)+(-4)+(-5)} ----> 4,5,0,-14 %e A110427 1 %e A110427 2 1 %e A110427 3 3 -3 %e A110427 4 5 0 -14 %e A110427 5 7 3 -10 -35 %e A110427 6 9 6 -6 -30 -69 %e A110427 ... %e A110427 Sequence contains the leading diagonal. %o A110427 (PLT DrScheme) %o A110427 (first (reverse (A110425 n)) %o A110427 ;;see A110425 for definition of that function. %o A110427 -- _Joshua Zucker_, May 10 2006 %Y A110427 Cf. A110425, A110426. %K A110427 easy,sign %O A110427 1,3 %A A110427 _Amarnath Murthy_, Aug 01 2005 %E A110427 More terms from _Joshua Zucker_, May 10 2006 # Content is available under The OEIS End-User License Agreement: http://oeis.org/LICENSE