cp's OEIS Frontend

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.

A188253 Number of arrangements of 7 nonzero numbers x(i) in -n..n with the sum of x(i)*x(i+1) equal to zero.

Original entry on oeis.org

40, 1284, 12692, 58824, 193232, 521124, 1142180, 2347608, 4323448, 7567844, 12129300, 19691552, 29057776, 42900188, 61593740, 86648240
Offset: 1

Views

Author

R. H. Hardin Mar 25 2011

Keywords

Comments

Row 5 of A188249

Examples

			Some solutions for n=4
..1....2...-3...-1...-1....1...-1....4...-1....4...-1....4...-1....2....4....3
.-2....1....3....3...-2....1....3...-1....1....3....2....4...-3....3...-3...-2
..4....4....4....3...-2....2....1...-4...-3...-3...-1....2...-3...-1...-4....1
..2...-4...-4...-4...-2....3....2....3...-1....1....1...-2....4...-1...-1....4
.-3...-4...-4...-1....1...-2...-3....3....2....1....4....4....4...-2....4....2
.-4....3....3....2...-4....1...-4....3....1....1....1...-2...-2...-3...-3....4
..1....2....3....2....1...-1....2...-2....1...-2...-3....2....4....4...-4...-3

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