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 A350296 #12 Dec 25 2024 00:51:25 %S A350296 0,1,3,7,13,20,28,40,52,66,82,99,117,140,164,189,215,243,273,304,336, %T A350296 376,414,454 %N A350296 Minimum number of 1's in an n X n binary matrix with no zero 2 X 2 submatrix. %F A350296 a(n) = A347472(n) + 1 = n^2 - A001197(n) + 1 = n^2 - A072567(n). %F A350296 a(n) >= A152125(n). %e A350296 Solutions for a(3)=3, a(4)=7, a(5)=13, a(6)=20: %e A350296 . . x . . . x . . . . x . . . x x x %e A350296 . x . . x x . . x x x . . x x . . x %e A350296 x . . x . x . x . x x . x . x . x . %e A350296 x x . . x x . x . x x . x . . %e A350296 x x x . . . x x x x . %e A350296 x . x x . x %Y A350296 Column 2 of A339635. %Y A350296 Cf. A001197, A072567, A152125, A227133, A347472. %K A350296 nonn,more %O A350296 1,3 %A A350296 _Andrew Howroyd_, Dec 23 2021 %E A350296 a(22)-a(24) computed from A001197, added by _Max Alekseyev_, Feb 08 2022