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 A225011 #14 Mar 09 2023 15:37:30 %S A225011 5,25,95,295,791,1897,4166,8518,16414,30086,52834,89402,146446,233108, %T A225011 361711,548591,815083,1188679,1704377,2406241,3349193,4601059,6244892, %U A225011 8381596,11132876,14644540,19090180,24675260,31641640,40272566,50898157 %N A225011 Number of 4 X n 0..1 arrays with rows unimodal and columns nondecreasing. %C A225011 Row 4 of A225010. %C A225011 Apparently also column 5 of A071920. - _R. J. Mathar_, May 17 2014 %H A225011 R. H. Hardin, <a href="/A225011/b225011.txt">Table of n, a(n) for n = 1..210</a> %F A225011 Empirical: a(n) = (1/40320)*n^8 + (1/1440)*n^7 + (3/320)*n^6 + (5/72)*n^5 + (629/1920)*n^4 + (1279/1440)*n^3 + (16763/10080)*n^2 + (25/24)*n + 1 = 1 + n* (n+1) *(n^6 + 27*n^5 + 351*n^4 + 2449*n^3 + 10760*n^2 + 25052*n + 42000)/40320. %F A225011 Empirical: G.f.: -x*(x^4 - 5*x^3 + 10*x^2 - 10*x + 5) *(x^4 - 3*x^3 + 4*x^2 - 2*x + 1) / (x-1)^9. - _R. J. Mathar_, May 17 2014 %e A225011 Some solutions for n=3 %e A225011 ..0..1..0....0..0..0....0..0..1....0..0..0....1..0..0....1..0..0....0..0..1 %e A225011 ..0..1..1....0..1..0....0..1..1....0..0..0....1..0..0....1..0..0....0..0..1 %e A225011 ..1..1..1....0..1..0....1..1..1....0..0..0....1..1..0....1..0..0....0..0..1 %e A225011 ..1..1..1....0..1..0....1..1..1....0..0..1....1..1..0....1..1..1....0..1..1 %Y A225011 Cf. A071920, A225010. %K A225011 nonn %O A225011 1,1 %A A225011 _R. H. Hardin_, Apr 23 2013