This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.
%I A188325 #7 Jul 22 2025 11:07:32 %S A188325 0,1,2,10,40,197,980,5142,27632,152191,853564,4863492,28075992, %T A188325 163920550,966421928,5746596806,34428962746,207654949801, %U A188325 1259963104618,7686160299232,47116518171284,290105437233107,1793451033655758 %N A188325 Number of nondecreasing arrangements of n nonzero numbers in -(n-1)..(n-1) with sum zero. %C A188325 Column 1 of A188333 %H A188325 R. H. Hardin, <a href="/A188325/b188325.txt">Table of n, a(n) for n = 1..32</a> %e A188325 Some solutions for n=6 %e A188325 .-5...-4...-5...-4...-4...-4...-5...-4...-4...-3...-5...-5...-5...-2...-5...-2 %e A188325 .-3...-2...-4...-2...-4...-2...-3...-2...-3...-2...-1...-4...-3...-2...-3...-2 %e A188325 .-1....1....1...-1...-1....1....2...-1....1...-1...-1...-4...-3...-2...-1...-2 %e A188325 ..1....1....2....2....1....1....2...-1....1...-1....1....3....1...-2....1...-1 %e A188325 ..3....2....2....2....3....1....2....3....1....3....2....5....5....4....4....2 %e A188325 ..5....2....4....3....5....3....2....5....4....4....4....5....5....4....4....5 %K A188325 nonn %O A188325 1,3 %A A188325 _R. H. Hardin_ Mar 28 2011