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.

A201698 Number of nX6 0..2 arrays with rows and columns lexicographically nondecreasing read forwards and nonincreasing read backwards.

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%I A201698 #7 Jul 22 2025 16:19:12
%S A201698 3,48,2068,167625,14268351,795339012,27102769900,615440785548,
%T A201698 10106227864338,127441635892627,1290114077123683,10846768837607450,
%U A201698 77797729805055016,486398599750167133,2697872438447793007
%N A201698 Number of nX6 0..2 arrays with rows and columns lexicographically nondecreasing read forwards and nonincreasing read backwards.
%C A201698 Column 6 of A201700
%H A201698 R. H. Hardin, <a href="/A201698/b201698.txt">Table of n, a(n) for n = 1..90</a>
%F A201698 Empirical: a(n) is a polynomial of degree 34
%e A201698 Some solutions for n=3
%e A201698 ..0..1..1..2..2..2....1..1..2..2..2..2....0..1..1..1..1..2....0..1..1..1..2..2
%e A201698 ..2..0..1..0..2..2....2..2..1..1..2..2....1..1..1..1..2..0....2..0..2..2..0..0
%e A201698 ..2..2..1..1..0..0....2..2..2..2..1..1....2..1..1..1..0..0....2..2..0..0..0..0
%K A201698 nonn
%O A201698 1,1
%A A201698 _R. H. Hardin_ Dec 03 2011