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 A202958 #7 Jul 22 2025 16:53:28 %S A202958 36,268,1562,9884,66208,447528,3020170,20430512,139027620,950710524, %T A202958 6520317018,44823140280,308853569150,2132736199028,14754220477302, %U A202958 102231808797944,709381651755672,4928801328948764,34285920139143690 %N A202958 Number of arrays of n+2 integers in -4..4 with sum zero and adjacent elements differing in absolute value. %C A202958 Column 4 of A202962 %H A202958 R. H. Hardin, <a href="/A202958/b202958.txt">Table of n, a(n) for n = 1..210</a> %e A202958 Some solutions for n=5 %e A202958 ..2...-3....0...-3....0....1....2....4...-2...-3....0....1...-3....4...-1...-1 %e A202958 ..3....1...-1...-1...-3....0...-3...-3....0...-1...-4...-2...-4...-2....4....0 %e A202958 ..0...-2...-3....0...-4...-1....4...-4....4....3....1....1....3....0....2....2 %e A202958 .-1....1...-2....3....2....4...-1....1....2....2....4...-4....0....3....1...-1 %e A202958 .-2....2....1....4....0....0....3....3....1....1....3....0....3...-2...-3...-3 %e A202958 ..1....4....4...-1....1...-4...-4....1...-3...-3....0....1...-2....0....0....4 %e A202958 .-3...-3....1...-2....4....0...-1...-2...-2....1...-4....3....3...-3...-3...-1 %K A202958 nonn %O A202958 1,1 %A A202958 _R. H. Hardin_ Dec 26 2011