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A187991 Number of nondecreasing arrangements of 7 numbers x(i) in -(n+5)..(n+5) with the sum of sign(x(i))*2^|x(i)| zero. 1

%I #11 Jul 23 2023 22:22:28

%S 411,632,912,1257,1673,2166,2742,3407,4167,5028,5996,7077,8277,9602,

%T 11058,12651,14387,16272,18312,20513,22881,25422,28142,31047,34143,

%U 37436,40932,44637,48557,52698

%N Number of nondecreasing arrangements of 7 numbers x(i) in -(n+5)..(n+5) with the sum of sign(x(i))*2^|x(i)| zero.

%C Row 7 of A187988.

%e Some solutions for n=3:

%e -7 -8 -7 -1 -6 -8 -8 -7 -4 -6 -7 -5 -8 -7 -8 -6

%e -4 -5 -2 -1 -3 -5 -6 -5 -2 -3 -5 -3 -3 -7 -3 -5

%e -4 -1 -2 -1 -1 2 -1 -3 -2 -3 4 1 -2 -7 -3 -4

%e -4 0 1 -1 1 2 0 3 -2 2 4 1 -2 6 4 4

%e 4 0 1 1 2 3 0 5 -1 2 5 1 3 6 6 5

%e 5 5 2 1 2 4 6 6 -1 3 5 1 3 7 6 5

%e 7 8 7 2 6 8 8 6 5 6 6 5 8 7 7 5

%K nonn

%O 1,1

%A _R. H. Hardin_, Mar 18 2011

%E a(26) corrected by _R. J. Mathar_, May 11 2023

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Last modified September 7 11:06 EDT 2024. Contains 375730 sequences. (Running on oeis4.)