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 A202075 #7 Jul 22 2025 16:28:23 %S A202075 44,560,1786,0,95342,1264272,4213042,0,241384794,3259289000, %T A202075 11028760078,0,651843679214,8881641917904,30295985735960,0, %U A202075 1822122857478000,24962501190898560,85571276146432860,0,5204404120691796724 %N A202075 Number of arrays of n+2 integers in -7..7 with sum zero and the sum of every adjacent pair being odd. %C A202075 Column 7 of A202076 %H A202075 R. H. Hardin, <a href="/A202075/b202075.txt">Table of n, a(n) for n = 1..210</a> %e A202075 Some solutions for n=3 %e A202075 .-4....4....4....2...-6....2....4...-6...-4...-2....2....0....0...-2...-2....2 %e A202075 .-5...-5....7...-5....5...-1...-5....7...-3....7...-3...-3....5....3....3...-7 %e A202075 .-2....2...-4....2....0....0...-2...-2....6...-2....6...-2...-2....4...-2....6 %e A202075 ..5...-3...-7...-5...-5...-3....7....1....1...-1...-1....5...-3...-7....1...-7 %e A202075 ..6....2....0....6....6....2...-4....0....0...-2...-4....0....0....2....0....6 %K A202075 nonn %O A202075 1,1 %A A202075 _R. H. Hardin_ Dec 10 2011