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%I #23 Feb 29 2020 04:21:28
%S 1,2,-2,3,-3,2,4,-4,3,0,5,-5,4,0,2,6,-6,5,0,0,0,7,-7,6,0,0,3,0,8,-8,7,
%T 0,0,0,0,0,9,-9,8,0,0,0,4,3,0,10,-10,9,0,0,0,0,0,-3,-2,11,-11,10,0,0,
%U 0,0,5,0,-3,2,12,-12,11,0,0,0,0,0,0,0,0,0
%N T(n, k) are the summands given by the generating function of A327420(n), triangle read by rows, T(n,k) for 0 <= k <= n.
%F Sum_{k=0..n} T(n, k) = A327420(n).
%e Triangle starts (at the end of the line is the row sum (A327420)):
%e [ 0] [ 1] 1
%e [ 1] [ 2, -2] 0
%e [ 2] [ 3, -3, 2] 2
%e [ 3] [ 4, -4, 3, 0] 3
%e [ 4] [ 5, -5, 4, 0, 2] 6
%e [ 5] [ 6, -6, 5, 0, 0, 0] 5
%e [ 6] [ 7, -7, 6, 0, 0, 3, 0] 9
%e [ 7] [ 8, -8, 7, 0, 0, 0, 0, 0] 7
%e [ 8] [ 9, -9, 8, 0, 0, 0, 4, 3, 0] 15
%e [ 9] [10, -10, 9, 0, 0, 0, 0, 0, -3, -2] 4
%e [10] [11, -11, 10, 0, 0, 0, 0, 5, 0, -3, 2] 14
%o (SageMath)
%o def divsign(s, k):
%o if not k.divides(s): return 0
%o return (-1)^(s//k)*k
%o def A327487row(n):
%o s = n + 1
%o r = srange(s, 1, -1)
%o S = [-divsign(s, s)]
%o for k in r:
%o s += divsign(s, k)
%o S.append(-divsign(s, k))
%o return S
%o # Prints the triangle like in the example section.
%o for n in (0..10):
%o print([n], A327487row(n), sum(A327487row(n)))
%Y Cf. A327420, A327093, A057032, A069829.
%K sign,tabl
%O 0,2
%A _Peter Luschny_, Sep 14 2019
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