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 A201493 #6 Jul 22 2025 16:16:22 %S A201493 12,7815,7798656,6697376240,4585552158911,2571822263246639, %T A201493 1219998885223727883,501770963443215883902,182271590618268117246577, %U A201493 59312881704712898493358018,17484065266324835514539288191 %N A201493 Number of nX5 zero-sum -2..2 arrays with rows and columns lexicographically nondecreasing. %C A201493 Column 5 of A201496 %e A201493 Some solutions for n=2 %e A201493 .-1..0..0..1..1...-1.-1.-1..0..2...-2.-1..1..1..1...-2.-1..0..0..1 %e A201493 ..0..0..2.-2.-1...-1..0..0..0..2...-1.-1.-2..2..2....2.-1.-1..0..2 %K A201493 nonn %O A201493 1,1 %A A201493 _R. H. Hardin_ Dec 02 2011